Is my iPhone hacked?

Okay I'm seriously not lying I went to the restroom like a couple of minutes ago and my phone was left completely on and I been feeling extremely paranoid lately. And it turned completely off I feel like I'm going insane. It was asking for my passcode but it wasn't acceptaing my finger print in the first place and my brightness was a bit down too. A couple of weeks back I gave my iphone a full reset to wipe out my entire information. And I stopped receiving messages from scammers. And now my phone has been heating when i use it at times but I feel like it can be the battery draining. My internet has been constantly slow lately and a bit of my data usage has been raised up. I don't know what's going on but my phone seems to be acting normal lately. But can someone help with this please? Also my speaker has been making a weird static noise when I don't use it at times and it was never done that before. Can someone please tell me what is going on?

Probably