I was diagnosed with infectious mononucleosis and strep throat about two and a half weeks ago. I was suppose to get my period on Saturday but I am now 5 days late. The last time i had my period was on the 8th of last month and i can be a little bit irregular. Last week i experienced all my usual symptoms of PMS but my period never came. I am sexually active but we always use a condom and check to make sure nothing leaked and their were no holes. Could I be late because of the mono or is that unlikely?