My gf has not taken her birth control in 5 days but took 1 pill yesterday and we had unprotected sex and i ejaculated inside of her? is pregnacy likey

Unlikely: It depends how long she had been taking the birth control pills before she stopped. If the 5 days were her usual hormone-free interval, then probably not. If she had not been taking the pills for more than a month, then a little more likely. If the pills she did not take were at the first of the pack (eg, started the pill pack 5 date late), then much more likely.