Yeah I'm ok. I have a bit of a cold, but I really didn't want to miss your class!
I would answer 'how are you feeling' with this sentence. 'A bit of a cold' is the most common way of saying 'a slight cold', the opposite would be 'a really bad cold'. A nice thing to add is 'I didn't want to miss your class' is a kind thing to say. By adding 'really' emphasises this sentence further.
私なら 'How are you feeling'（調子はどう？）に上記のように答えます。
'A bit of a cold' は 'A slight cold'（軽い風邪）の最も一般的な言い方です。その反対は 'A really bad cold'（ひどい風邪）です。
'I didn't want to miss your class'（あなたの授業を休みたくなかった）と加えるとすてきですね。'really' を加えると、さらにこの文を強調できます。
I didn't want to miss the lesson even though I have a touch of cold.
"want to 〜" は「〜したい」という表現です。より丁寧で控えめに言う場合は "would like to 〜" を使うと良いでしょう。
"miss 〜" は「(会議などに)欠席する、(仕事などを)休む」という表現になります。ここでは「一回のレッスンも逃したくない」という感情を表すことができます。
"even though 〜" は「〜であるけれども、〜にもかかわらず、たとえ〜でも」ということを表します。「実際に〜だけれども」といったニュアンスです。
"cold" は「風邪」を表し、"have a cold" で「風邪をひいている」となります。
"a touch of 〜" は「軽い症状の〜」という表現です。"slight"(極めて少量の、ほんのわずかな) を使って "have a slight cold" と言うこともできます。
I have a cold but it won't keep me from the lesson
My cold is not bad enough to be absent from the lesson
I have a slight cold, but I can do the lesson
If it is obvious you have a cold you can assure your teacher that you can continue with the lesson by saying, "I have a cold but it won't keep me from the lesson", "My cold is not bad enough to be absent from the lesson", "I have a slight cold, but I can do the lesson", and "I know I sound sick but I feel that I can complete the lesson."
風邪を引いていることが明らかなときには、次のように、レッスンが続けられることを先生に伝えることができます。
"I have a cold but it won't keep me from the lesson"
（風邪を引いていますが、レッスンは受けられます）
"My cold is not bad enough to be absent from the lesson"
（風邪はレッスンを休むほどひどくありません）
"I have a slight cold, but I can do the lesson"
（風邪気味ですが、レッスンは受けられます）
"I know I sound sick but I feel that I can complete the lesson."
（風邪声ですけど、レッスンは最後まで受けられると思います）
I am not feeling fully well but I didn't want to miss your lesson
I have a mild cold and so am not feeling well however I didn't want to skip your lesson because of it
I am a little unwell but I didn't want to skip your lesson because of it
"I have a mild cold and so am not feeling well however I didn't want to skip your lesson because of it" - this fully explains your situation but is slightly formal (perfect if you do not know the person well)
"I am not feeling fully well but I didn't want to miss your lesson"
"I am a little unwell but I didn't want to skip your lesson because of it"
Both sentences are slightly more casual ways of explaining that despite your slight cold you did not want to miss the lesson.
"I have a mild cold and so am not feeling well however I didn't want to skip your lesson because of it"（軽い風邪で体調はよくありませんが、レッスンを休みたくありませんでした）
- これであなたの状況を十分に説明できます。ただ、少しフォーマルです（相手がよく知らない人ならピッタリです）。
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"I am not feeling fully well but I didn't want to miss your lesson"（体調は万全ではありませんが、レッスンを休みたくありませんでした）
"I am a little unwell but I didn't want to skip your lesson because of it"（体調は少し悪いですけど、レッスンを休みたくありませんでした）
この二つの文の方が少しカジュアルです。どちらも、風邪気味だけどレッスンを休みたくなかったと伝えています。
I caught a bit of a cold but it doesn't prevent me doing this lesson
You planned to do a lesson and you have a very minor ailment which doesn't stop you doing anything. You want to mention that there was a possibility of you being absent from the lesson? You could use the verb 'skip' but if you 'skip' a lesson it somehow infers that you have a plan or an intention to miss the lesson. In this case 'miss' would be a better verb to use, or you could say:
Although I have a slight cold, it is not bad enough to force me to miss the lesson."
あなたはレッスンを予定していましたが、何かをやめるほどでもない非常に軽い病気になりました。レッスンを欠席していたかもしれないと伝えたいのでしょうか？'skip'という動詞を使うことができますが、レッスンを'skip'したと言うと、レッスンを休む計画や意図があったと推測されるかもしれません。この場合は、'miss'がより適切な動詞です。
【例文】
Although I have a slight cold, it is not bad enough to force me to miss the lesson."（軽い風邪を引いていますが、レッスンを休むほど悪くはありません）
I'm a little under the weather, but I don't want to miss the lesson.
I'm coming down with something, but I'm well enough to move forward with the lesson.
I have a slight fever, but I won't have to skip the lesson.
"A little under the weather" is an idiom that is used to admit one is feeling ill. Being well enough indicates that the illness is not too bad and won't keep you from the lesson.
To say one is coming down with something means that there are symptoms of an illness like a cold, but the symptoms are not so serious that it will keep one from missing out on a planned event.
A fever is an above normal measurement of the body temperature. It is an indication that one is ill. To describe it as slight means that it is not too bad.
"A little under the weather" は「体調不良の」という意味のイディオムです。
"Being well enough" は、病気がレッスンを休むほどひどいものではないことを表します。
"Coming down with something" は「風邪のような症状がある」という意味で、予定を取りやめなければならないほど深刻ではないものをいいます。
"Fever" は平常よりも体温が高いことをいい、病気の兆候の一つです。
"slight" は、症状が軽いことを表します。
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