I think it was some sort of garden bug. I couldn’t shift it and the dermatologists had no idea what it was. It started a few years ago when I got bit by mosquitoes on holiday. They left what looked like bumps on my arms. They didn’t really bother me at first but looking back I think they had burrowed into my skin. A few years later I was really itchy and had a crawling sensation on my skin. Anyway, I know the answer to get rid of them now. It is Hydrex which is Chlorahexadine - basically Hibiscrub which is a surgical scrub. I’ve been using Hydrex and all of these sensations have gone and the bumps are disappearing on my arms. I discovered this after researching intensively on the Internet. The scientists recommended Chlorehexadine for unknown mites on your skin. Also buy Dermol cream on the Internet to use once or twice during the day. It’s a really good cream. If you have bumps on your arms mix ground cinnamon powder, garlic powder and olive oil together and exfoliate the bumps. It was also a great way to get rid of these bumps. Good luck. It’s a nightmare but I know have the answer and relief. X