IUD or pregnant?

So I got a Mirena IUD in July and it was placed in properly with absolutely no complications. About a week and a half later I had sex with a guy I was dating...

We had been doing foreplay for a while and I told him to use a condom before sex. I can’t remember if he tried to go without one at first and put it in once or not which is why I’m worried

Either way he and I had sex with the condom on and he didn’t finish. I gave him a blow job and he finished in my mouth...

My obgyn used an in office ultra sound to check if my iud was in place and she said it was still in the middle and top of my uterus and could see the bottom so it was in place so it was working.

I haven’t gotten a real period since my IUD was put in so I wouldn’t have no clue if I missed it but recently my boobs have hurt, I get cramps, I’m nauseous and lightheaded....

Is there any chance I could be pregnant??