You have a heavy mite infestation. You're right, you are their host. They are using your body to feed f*** and breed. They are strong resilient and resistant to traditional pesticides. The bites you feel are the adult mites feeding the crawling sensations are from the eggs hatching and nymphs crawling hatching underneath your skin. They will not leave willingly. You have to fight. This is war. They have also infested your home cloths and car. Even if you find something that seems to work the relief is short-lived because still eggs hatching form within you. Mites infesting you from your surroundings and personal effects. I know because I went through 16 months of pure hell before I found triclosan powder. Use this to shower, lotion your body, fog your home, spray you mattress and wash your cloths. It's the only thing I found to kill them. It saved my life and it will yours too. In your post you mentioned another really important fact. That is something has gone horribly wrong in our environment. Climate change or maybe mutant mites? Either way, they have evolved to attack and feed on humans and they can withstand an arsenal of insecticides. Even natural ones that they are not suppose to build resistance to. More people are becoming infected at an alarming rate. For now triclosan powder works and is your ONLY salvation. They may eventually be able to build resistance to this too. Government and health officials know this thats why they are trying to ban it now. If this is what the coming pestilences look like, we already know millions will be living in pure HELL.