What does Perimenopause feel like?

I am 38 years old, will be 39 in a few days. I began menstruating at 11. I got my last period on 9/1 which was shorter and not as heavy as usual. My PMS symptoms are excessive fatigue and sore . My PMS symptoms have not gone away and my period has been gone since Friday. Instead of getting less sore or being not sore at all, my s are killing me! Even the shower is an issue. I have an appt with my ob/gyn this afternoon. I expect her to tell me perimenopause has begun since all the symptoms I am experiencing point either to that or pregnancy. I can't be pregnant, I had my period less than a week ago. Are these the types of symptoms you would experience when menopause begins? I thought I was too young to be going through this already. Any ideas?