Partner not wanting to be involved..

E • Baby No.2 baking,soon to have 2 under 2!
I'm 20 y/o I'm currently 8wks 6 days I have my first ultrasound at 10wks 1 day (next Thursday) and I told my partner and booked it so he would be able to come, he has no interest. We currently live with his parents and we have had a pregnancy before he was more into that pregnancy then this one. This time if I even mention it he basicly rolls his eyes and tunes out. I understand it's a huge thing to get his head around seeming we weren't planning to get pregnant, but it's huge for me too. I'm just over feeling alone about it.