I went through his phone

I need some advice. We had a Halloween party last night and obviously I’m 5 1/2 months pregnant. So while my boyfriend/unborn babies Dad enjoyed himself I just hung out and was the party mom. I had his phone all night so he wouldn’t lose it and he kept getting a few texts from his guy friends. I don’t know why I decided to go through his phone but it happened, it was the first time and I guess curiosity got the best of me. About 2 months ago his ex girlfriend of 8 years texted him and congratulated him about us having the baby. They’ve been broken up for He texted her back and said something along the lines of “thanks it’s not who I wanted it to be with though” and she replied with he’s stuck with me forever now, and then they had a conversation from there about how each other has been. My boyfriends older sister was at the party and we are pretty close and she could clearly see I was upset so I showed her the texts and she said she didn’t understand because he tells her everything and every time she asks him if he’s happy he always says he is and he is glad everything is going the way it is with me and every time he talks about his ex he always says how she treated him so shitty. (She was an alcoholic and would treat him horribly, not to mention she cheated on him and kicked him out of their house after he found out). Hes a very straight forward person and always says if he wasn’t happy he would say something and that he wouldn’t beat around the bush with me. I’m emotional as hell already being pregnant , and I’m not too sure how I’d even be able to say anything to him without bawling my eyes out. Him and I were supposed to be moving into our own house next weekend and preparing for the baby. I’m not sure what to do. I want to bring it up to him because I obviously feel like he’s not happy now, but I know he may be irritated I went through his phone. He can tell something’s wrong with me today, as I’m being kind of distant but I don’t even know what to do or how to go about saying anything to him.