Paxlovid works by interfering with viral replication. If you still have detectable levels of virus in your system (e.g. blood PCR test) there is some chance it might help--talk to your doctor!

If you have no evidence of any remaining virus in your system, your symptoms may at this point be fully auto-immune in nature, and/or the result of already-inflicted damage, and it is very unlikely that blocking viral replication would help. (However, it's still marginally possible that paxlovid is cross-reactive with some other virus that is in your system...so you couldn't completely rule out that it might have a positive effect. But you also can't rule out negative side-effects! Biology is complicated. Talk to your doctor, who doesn't know everything because there is too much to know and there is far more unknown than known, but who is still likely your best guide. A second opinion is often valuable--sometimes a different perspective helps find a solution.)