Is it possible to be pregnant?

I should start with the fact that I have the Skyla IUD.

My boyfriend and I had sex on Nov 23 and he finished inside of me. I started to spot on Nov 26. I’ve been super nauseous and had hot flashes since, but those sometimes happen with a period. I also have frequent migraines and have noticed that I’ve felt a few coming on.

We are concerned about the possibility, even though it is low, that I might be pregnant.

Any thoughts on this? I am planning to test by the end of this week but thought I’d check here for support as well.