When he starts switching up on you

I been with my boyfriend for a while now. Finally conceived a baby, which he wanted more than anything. I found out I was pregnant after a miscarriage just a few days ago. He’s been really agitated and aggressive with his words. I been calm, nice, and happy as possible to avoid losing this baby too. But he snaps so easily on me now and I don’t understand. Starts yelling at me bc I made a dr appointment for next week vs skipping work today to go.. I calmly explained work is important right now and calling in 30 minutes prior to my scheduled time is unprofessional. I hung up in his face bc he started to yell. I sent a text stating he cannot y’all to me that way especially since I didn’t do anything to deserve it and I pleaded him to cut his shit. He responded, I’m ignoring you like you did when you hung up in my face...

Where did this guy come from?! He was so perfect. And the last week being around him is terrible... idk if it’s the reality of the baby sinking in, or if something else is bothering him and he’s taking it out on me.. either way, I don’t deserve it. Now if I was being a bitch to him, that’s different. But for no reason is really starting to hurt me