PLEASE HELP- I’m freaking out

My daughter just turned 6 months old on the 4th. Recently, I’ve noticed that she doesn’t want to make eye contact with many people when we are out. It’s almost like she gets overwhelmed. Now she’s gotten to where she sometimes won’t make eye contact with me. She also flinches and blinks when she hears loud noises. Sometimes she looks at me and smiles and even laughs. She babbles and screams. Other times she will go out of her way not to look at me. She tracks my face when she looks at me, and she tracks toys, but I can’t help but worry about it. It’s like she’s interested in everything but me. I’m constantly worrying about it, today I laid in the floor with her and just cried. Obviously an autism diagnosis wouldn’t be the end of the world, and I don’t want to offend anyone with a child Or children on the spectrum, but i am so scared. I have been crying about it every day for the last week. It’s become an obsession. We go to the doctor for her 6 month check up next week. Does anyone have any insight or advice? I just want to calm down.