Why do my hands get hot,red, and itchy?

Im 14 going 15 and this has been happening for years on certain occasions. Sometime when Ive been holding something or carrying something that puts allot of wait on my hands or pushes hard on my hands(for example vacuuming, taking out trash, etc etc...) my hands will get hot and most of the time itchy. Its terrible during the winter when my hands are exposed to the cold weather they also get red and itchy. Also sometimes my fingers(most of the time my thumbs) well get swollen for no reason and most of the time sore. Now the first one when usually wears off within a couple of minutes after the pressure is taken off of my hands, the second one I really dont remember since its summer time and I usually dont take the time to see how long it takes(because it too eventually wears off), and the third one(the most annoying one) sometimes takes until the next day to wear off. I already know what causes the first two but the third is a complete mystery to me. What I want to know is what all three are, what causes them, how to prevent them. Ive told my mom about it a few times but she always says as long as they wear off Im find, and maybe she's right but just to be on the safe side I would really appreciate it if you guys could help me out.