I feel like utter crap

So I've spent the better part of the last 18 years being tired but the last few weeks have been the absolute worst. I am SO drained, I am constantly dizzy and I even have to take breaks just while cooking or dishing up food! I get so out of breath and weak, I can't even. I know I need to make a doctors appointment, and I will for next week sometime. I can't ever remember a time that I've been this tired.