Is this normal?

Two questions....

So I got my iud like 3 weeks ago and a week after me and my boyfriend had sex and I don’t know what happened but he might have went too deep but instantly I started to cramp up and I couldn’t see because everything went black and I fainted. I was in so much pain for about an hour literally laying on the bathroom floor butt naked crying. And I couldn’t stand up because if I did I would faint again. Anyways the day after I started to bleed and ever since I’ve been bleeding. Normal? Next question if this is just my period can tampons hurt my stomach? Because when I have one it my stomach hurts really bad and when I take it out it’s magically all better? Let me know what you guys think or if it’s happened to you before.