relapse after four months at 100% recovered

hi everyone,

I got long COVID last August after a relatively mild case of Covid and was ill for seven months — some bedbound but mostly housebound. I recovered over the course of two months thanks to mind body work and have since returned to full time work, walking and traveling. a couple of days ago I rode my bike for the first time because I was late to something and didn’t want to take an uber. I don’t know if I’m sick (I tested negative for COVID) or what but for the last three days I’ve been hit with the same terrifying sensations: heavy body, exhaustion, high heart rate, brain fog and soreness. it keeps getting worse with each day, too. yesterday i was tired but now I’ve got that weak and poisoned feeling. I’m trying not to freak out because I can’t do another 7 months of this hell and don’t know what to do. I was literally fine three days ago and now I’m back in hell. has anyone dealt with this before? what should I do? I feel like I’m going to break down in tears.