It's impossible to have a period and be pregnant. Some women might experience light bleeding/spotting but this is NOT a period. Hence why you're not pregnant since you had a period. Like I said before, you only had sex 4 days before your period was due to begin - ovulation has already occurred so you can't conceive here. So you saying some women are different makes no difference at all - it's just not possible.
You're right those things can be considered signs of pregnancy, but they're signs of other things too - PMS, a virus etc so you can't say you're feeling those things because of pregnancy because they don't determine you being pregnant. End of the day, you got your period, and the timing of sex wasn't the best time to conceive either so you're not pregnant.
If you are unsure you can take a pregnancy test however its probably just nerves.
then how will you explain the eatin more than usual the really tight feeling in my stomach the nauseating tender boobs that is all the signs of pregnancy
You are most likely not pregnant if you had a period
some women are different though
No, you're not likely to get pregnant just before your period starts since ovulation has already occurred.