X-ray and antibiotic

I'm 35 weeks and I've been worrying a lot lately because I overthink everything. Around 20 weeks I had to have a foot X-ray because I could barely walk I thought I fractured it and just last week I was given a Z-Pack for a sinus infection, I also took a Z-Pack in first tri for a sinus infection as well. I just read something online saying radiation can cause sever birth defects. I haven't had an Us since week 18 so now I'm worrying bc I had an X-ray after that. My OB said it was fine to do and they were the ones who recommended it to begin with. Does anyone have any insight or experience on this topic?