If my boyfriend came and then wiped his hands off on the sheets and after about 5 or so minutes touched the top of my vagina ... could i get pregnant ?

Very unlikely, but: The time of your ovulation is the key. Also the vitality of his sperm matters. Most cannot survive in the air even a short time. But some can and if they did and were great travelers and got to your fertile egg at the right time - yes. But it's a very low possibility. If you're late w/ your next period, do a test. Be more careful if you want total security.