What Are The Chances Of Pregnancy Post Unprotected Sex Despite Having Plan B?

i had sex around 2am on about day 22 of my cycle. my last period began on nov 9 and ended on the 15. my periods last almost always 7 days and are typically 28 days long. which would mean i am supposed to start my next one on the 7th (in 3 days)
he used a condom the entire time. we stopped for a little (he did not ejaculate) and i made him put a new one on just in case. i do not believe either condom had holes and he pulled out way a head of time when we finished. i got scared the next day and took plan b around 12 pm- about 10 hours later.
i am not on hormonal birth control because i very rarely have sex and i worry about the side affects. i'm only 22 and still in school so i panic every time i have sex which isn't very often to begin with, although i have never had unprotected sex.
what are my chances of pregnancy? i just need some reassurance as the waiting and uncertainty almost makes me physically sick.

Also- (this happened 5 days ago….i don't believe it's early enough for pregnancy symptoms, but i have felt very lethargic since. i've been bloated, had indigestion and stomach cramps-not like menstrual cramps but in my stomach, like i've been doing sit ups…. and a little bit of breast sensitivity. i know these could also be from plan b as well as the stress i'm putting on myself over this. I've had no bleeding but like i said, i am supposed to start my period in 3 or 4 days)