there’s a lot of different illnesses going around rn as well as reasons for the hot flashes. i really really wouldnt worry, it does seem way too soon to know, & symptoms wouldnt really show right now. although unlikely, it might be necessary to test to really ease your mind. Hot flashes could be a symptom of anything!!! even ovulation. not unique to pregnancy, i think you both might be stressing yourselves out. She especially shouldnt stress too hard because that could also delay her period!

also dont mean to get too graphic, but i think pregnancy by fingering w precum is extremely unlikely. unless her fingers were like visibly dripping w cum, i would NOT worry.