Yes, I get the same way and I always "get sick" before my period. Hormones do some crazy things to you. I'm also turning 40, however, and for me the hormone fluctuations could be along a different line than for you. I never had these "sick attacks" before my period until this past year or so.
And just like you, they last for a few days before, I get migraines almost like clockwork (that's how I know I'm going to start), feel feverish, nauseous, achey, and the regular PMS stuff like my boobs hurt, crampy, etc., -- I'll even get constipated, very sleepy...
And just like you, it goes away, and I'm fine.
This is also an important and very real hormonal fluctuation that can be measured, and if you exercise, you'll notice that right before your period you are at your absolute weakest. This is not the time you want to do anything physical. But right after your period starts you will have hormonal changes where you'll bounce back and feel actually stronger than before!
It's normal. I think it's just that some women react differently, perceive the sensations differently, and feel differently ABOUT those changes.