Whats wrong with my legs?

when i have been standing up for too long, my legs go all purple and red splotchy, and sometimes tingle and itch. im really self conscious about it, and often get asked 'whats wrong with your legs?', and i reply that i just have bad circulation...is this true? if it makes any difference, i am a very red person. my face is almost always red, even when im not hot or embarrassed. also, when i cross my legs i get red marks where my legs have been. i have tried lofas, and scrubbing legs in the shower but nothing works. i really hate it and even put foundation on my legs for the summer concert. what is this and how can i help it! thanks