(((((((((HALLIEBETH)))))))))))))))

It could be stress, it can cause it to fluctuate. If your body is under any sort of stress (like if you've lost a good amount of weight in a short period of time) then that can also affect it. Also could just be hormones... it happens.

I know that seeing a doc, especially for that sort of thing isn't fun but it's a good idea - just in case to rule out anything serious.