you dont really need to do things like double mask if you can get an N95 mask and wear it properly. here they have them in home depots and stuff, 3M is a good brand. ordering on amazon is risky because theres so much counterfeit shit but theres other good online vendors. the 95 stands for 95% filter effectiveness but in testing these things all hit over 99%. and yeah, sorry to hear about the trouble sleeping. i read one thing that even with mild cases, post-covid symptoms are common (it's at like 40% among unvaccinated people according to one thing i read) and the post covid symptoms can be basically anything, it's very weird