If I don't have nose drops, my nose gets so blocked up that I can't sleep.
If I don't use my nasal spray, my nose gets so blocked up that it is difficult to sleep.
At night, if I don't use my nasal spray I can't sleep because my nose gets so blocked up.
「点鼻薬がないと鼻が詰まって寝られない」＝ If I don't have nose drops, my nose gets so blocked up that I can't sleep. / If I don't use my nasal spray, my nose gets so blocked up that it is difficult to sleep. / At night, if I don't use my nasal spray I can't sleep because my nose gets so blocked up.
ボキャブラリー
if I don't have ＝ ～がないと
nose drops/nasal spray ＝ 点鼻薬
get blocked up ＝ 詰まる
can't sleep ＝ 寝られない
if I don't use ＝ 使わないと
difficult to sleep ＝ 寝づらい
at night ＝ 夜
イギリス 
