I feel like a trapped animal in a cage, why?

I feel like an animal trapped in a cage I have been feeling this way for the past year but it gets more and more intense. i get anxious being in civilization and just want to leave and go where there is just regular nature and be animistic and free. I'm very outdoorsy and just want to get away and be where there is no modern people just escape and have to live like a prehistoric human or an animal. its very intense and more than just a oh lets go camping kind of thing what is going on?