My teacher got angry with me because I kept writing my test even though the time was up.
My teacher was upset with me because I continued working on my test after our time was up.
1) My teacher got angry with me because I kept writing my test even though the time was up.
「時間が過ぎたのにテストの答えを書いていたので、先生に怒られた。」
2) My teacher was upset with me because I continued writing answers on my test after our time was up.
「時間がきてもテストの答えを書いていたので、先生に怒られた。」
「先生に怒られる」は
My teacher got angry with me
My teacher was upset with me
と言えます。
time is up で「時間がきた」
ご参考になれば幸いです！
I continued answering questions even after the time was up and the teacher got angry with me.
少し長くなったので、区切って説明します。
I continued answering questions → 回答を続けた
この部分では、answering questionsを取りぬいても意味は通じます。I continuedだけで（テストを）「続けた」という意味になります。
Even after the time was up → 時間が過ぎても
the time is upというのは、「時間切れ」という意味です。
The teacher got angry with me → 先生に怒られた
「怒られた」はgot angry with meでも、scolded meでもいいです。scolded me は「叱られた」という意味になります。
日本 
アメリカ合衆国 
