I need parents familiar with autism advice please

So I have 4 kids. A 5 year old boy, 3 year old boy almost 4, 21 month old daughter, and 6 month old daughter.

I started noticing when my 21 month old daughter was a baby that she wouldn’t support her neck when you lifter her by the arms. She kinda just did the flop thing ( I can’t remember what it’s called). And now at 21 months old she doesn’t talk at all. She says “ cheese, dadda and hi” that’s it and that’s pretty rare. She mostly just screams( a majority of the day is her screaming, or grunting. sometimes she will babble. She will point to things that I’m talking about and respond when I ask her things. She also makes eye contact and plays with others. But she also does a thing with her hands where she uses her middle finger to bend her pointer finger backwards on both hands and walk around doing that. She also throws really violent tantrums. And at the playground she only wants to play on the swing or walk around the perimeter, not actually play on the playground with other kids or by herself. I know some of this may be nothing. My other kids were just wayyyyyy ahead of her at this age and I’ve been putting of the speech thing for a long time now but I know I need to address my concerns at this point to a doctor and get speech therapy for her or whatever is needed. I just wanted to ask if anyone else had any similarity in an autistic child . My husband gets really angry anytime I try to bring it up and makes me feel stupid. But I don’t want to ignore it if this is something we need to help her with. Thank you for any help. And yes I am also scheduling an appointment with a doctor, I know no one can diagnose my daughter here or anything like that. I just wanted to try to find support and maybe a similar experience.