Why does pregnancy make me so sensitive

I’m so tired of being so quick to get hurt or upset. If my fiancé leaves a sock on the ground I can feel my blood start to boil. If his video games are too loud, I get annoyed. This morning I saw on Instagram he followed this girl he probably went to school with who’s gorgeous and posts half naked pics and I literally nearly cried.

I get frustrated with everything else but I feel like majority of my irritation is directed at him most of the time and I hate it. I feel like it’s making me pull away from him and be distant in our relationship. Our little girl is due in three weeks and the last thing I need to be worried about is our relationship being rocky due to the constant tension..

What can I do to ease my mind?