I am 22 years old. I get my periods every month regularly it varies from due date. Sometime its 2-3 early than due date or delayed by 2-3 days from due date.in jan after my periods got over on first day I had protected sex and this month in feb I did not get periods its been 13 days late from the due date. I had 3 pregnancy tests on 3rd day 8th day and 13th day after missing periods bt all results were negative. My right cheek has swollen there is some ulcer type of thing in my mouth on right side of cheek it is painful. Is it bcz the heat which had to come out with periods is coming out by way of ulcer? Or if m pregnant?