Unfortunately, the only microscopic bug (a mite), that I can think of is scabies. See a dermatogist (Dra. Daniela at Quality Care is very good) who can quickly identify and treat your condition, whatever it is. Not caused by poor hygiene, but possibly from touching a street dog or street cat? The best treatment for surfaces would be all natural, superheated steam, this is also very effective on bedbugs and dust mites.