Infantile spasms?

So, when my daughter was a few weeks old she had what I, at the time, thought was a breath holding spell. She tensed her entire body up, tucked her arms in, and was wide eyed. I called EMS and they checked her out and said she was okay and I made an appt with her ped the next day. They said it was caused by for bad case of acid reflux and brushed it off but I didn't feel like that was right. For the next 2 months she continued to do this about once or twice a week, and I realized she was still breathing when she did it but very very shallowly.

Then around 4 months old she stopped doing the tensing up and instead it was like her startle reflex came back. Everytime she was flat she would throw her arms out and flinch her face. I didnt ask the doctor about it because I figured it was just her startle reflex.

Now today at 5 months old, I initially thought my cousin's son was messing with her too much.because he kept yelling boo at her and I told.him to go away. Well for the next hour after he "played" with her she kept flinching like how someone would flinch before being hit in the face (and no before anyone asks, she has never been hit or dropped). She kept doing it for no reason. So I held her up and talked gently to see if she would stop but she kept doing it. But it was like it did t phase her. She would be babbling and blowing spit bubbles then flinch..then go back to babbles and flinch and so forth.

I was concerned so I of course went to google and some of what I've read is that all these things that have happened since birth could be signs of Infantile Spasms which is a form of epilepsy.

I'm the typical first time mom and I always am afraid of things being wrong. But this has me genuinely worried.

Have you or anyone you know had a child with this diagnosis?

My daughter's doctor treats me like I'm crazy and overprotective so I'm not sure how to get her to REALLY listen to me.