Feeling icky...

Week late for my period. Negative test. Started getting light cramps and sore nipples yesterday. I'm convinced I'm not pregnant just because how many times I've been let down, but I don't know why else I'd be late. I just know I'm not feeling well at all. Very lightheaded, nauseous, no actual vomiting though, and TMI, but extremely smelly gas. I just want to sleep.