I fingered my gf after i stimulated myself

Hi, My girlfriend and I were messing around to celebrate the booking of our holiday.We are both 20. What happened was she started to wank me and give me a bj.Then I asked her to stop to tease her and i just wanked a little in front of her. We heard a noise and I quickly got my clothes on. I checked and found no1 there.I cam back to the room and stripped off again.I then fingered my GF and in the middle of it she asked if I had used the same hand as I did when i was wanking. I said yes. But upn research I found that sperm dries within a couple of minutes and im 99% certain I didnt even cum. MY GF said I precame a little in her mout but i didnt feel that.My hand (if it had any precum on it) was exposed to the air for around 2-3 minutes and my hand was dry before I fingered her. Could she be pregnant ? Her period doesnt start until 10 days from now. And her ovulation period is 14 to 19. This happened on night 18/19 .Any help would be great thanks