Period question

I have a odd question and I'm not quite sure what to do. Okay, last month was the first month my period only lasted 3days, this month is the second time it's happened, however this is the first month in a year that my period has been five days late. My boyfriend had me take a test and it was negative. I'm not sure what to do about what happened. Second, last night I got extremely hot and I almost passed out, my temp spiked really high, and before it happened, my teeth really hurt like something had smacked me with a baseball bat. I'm not sure if it had anything thing to do with my period or what's been happening. I just really need advice before I make a appointment with a obgyn.