I just had sex and it felt very tight and uncomfortable. after that i received burning for about 20 minutes in my vagaina. ?

Surprise!: Surprise! Sex is not what your expected? Yes, the vagina will be snug initially and after ejaculation with vigorous intercourse, there may be "burning.". I hope you used a contraceptive method(s) to ensure there will not be an unintended pregnancy. If not, go see a GYN MD about that plus your previously stated concerns to rule out any abnormalities.