I am 54 years old, and I have uneven periods each month. Sometimes, I ve skipped them altogether. For the last 2 days, my period has been bright red and heavy. Today, since about 10 this morning, I ve felt light headed, shakey, and there s kind of a gnawing, tight feeling down below my sternum--I m thinking it s coming from my stomach area. When I walk around, I m not quite dizzy, but I feel as though I could faint.