It sounds like to me that your body is pretty new to capsicum. I'd slow back and start putting small amounts on my food if I were you. It's very alkalizing to your body and shouldn't cause adverse reactions in your body - unless you're not only not used to it - but your circulation is seriously subpar. Hmmm - I'd look to a few other issues to beef up your circulation. Why is your circulation so sluggish?
Maybe look to Butcher's Broom or Hawthorn first - then back to capsicum. If you need to clean some crud out so your blood moves more easily first - that's totally understandable. Is your lung chi low or something? That's another thing to look to.
Trapper's a big proponent of cayenne. I searched within his forum for a good link to post here about cayenne, what it's good for and how to use it - but there were too many, so I'll just post the search link: