So my skin has been really dry, especially the thigh area. i've been skin crawling and biting sensations and frequent muscle twitching. what is this?

Eczema : Eczema, (think extra sensitive dry over reactive skin) gets much worse in the winter, especially areas that rub. The itch associated with this can seem to be an unnatural pain. This is because the nerves in the skin are in a sense wired differently. This may not be your problem and doesn't explain muscle twitching so have it checked out by your doctor. Use lots of moisturizers, avoid scratching.