Chance of pregnancy?

Okay so I'm stressing a little bit. I'm sixteen and I've been seeing this boy for about two months. We havent had sex yet. I have given him a hand job and he's fingered me. So my issue is I made him cum the other day and it got on his upper arm and on the couch a little bit but he cleaned it up almost right away. And then not immediately after but a few minutes later he fingered me. I really don't think any seman came in contact with my privates in anyway. Now my period, although I've had it for over three years, it is extremely irregular. I track it best I can through an app on my phone and it is telling me I'm about fourteen days late (the event itself happened about three weeks ago) that same night we cuddled in our underwear although again I don't think anything was transferred. Do you think there's a chance I could be pregnant? And if so how likely is it? Thanks.