Am I being petty?

So, my baby daddy has another child. She's 2 or 3. When I told him I was pregnant he asked me to get an abortion, when i said no he told me he wanted nothing to do with the baby. I didn't talk to him for two months and then he came back and apologized and said he wanted to be around for the baby. I forgave him and have been working through my anger I had towards him for leaving me alone in a very hard time. Things have been fine and we've been getting along, but I still just sometimes feel alone when it comes to this pregnancy. He hasn't come to any of my doctors appointments... Which isn't a huge deal cause they're usually quick anyways. However I would've liked for him to come to my 20 week ultrasound.... He said he would and then the night before he got stuck late at work and ended up not coming. He works third shift as a police officer and ended up being at work till 9AM, my appointment was at 10AM. I was kinda pissed for the day but I let it go. I know he has a lot going on and he had to be back at work later that day. But it still hurt cause that was my last ultrasound. I scheduled my maternity tour of the hospital and asked him if he wanted to come with me and he said "definitely not, I've spent way to much time there." Kind of annoying, but whatever. So I go to my tour lastnight and It really wasn't anything new to me, but im glad I went. He texted me today saying "sorry you had to go by yourself" and I just said its fine... But the more I think about it the more annoying it is to me. Like I get he's gone through this before but it's my first time and I need support. I don't want to feel like I'm a burden to him because I'm asking him to be a part of this. I don't know... Maybe I'm over thinking it. Feeling kind of hormonal today and to add to it he's barely talked to me in the last few days. Am I crazy?