1) you have to know that it took long to get my sense of smell back also,
2) i am informed by my medical friend that the anitbody test is highly inaccurate, which means that even if you are immune to the virus, you can still show no anitbodies, in other words the antibody test means nothing.
3) if you tested for coronavirus and see that you are negative then you dont have it. Thats a fact.
therefore it might all be in the mind, my advice to you is to relax and enjoy an ice cream, listen to some music to lift your mood a little, learn something light to get your mind into something else. you can make yourself sick with your mind also, its a metsius and proven, if you look at john sarno’s book you will see that its proven. the Main thing is todaven to Hashem that Your Daas should be calm and not go against you and make you unhealthy. You should have arichus yomim vshonim tovim and have hatslacha in all your endeavors