Your possible exposure on 1991,almost 25 years before from now,your multiple tests shows your negative for hiv,then why are you worrying unnecessarily? if you dont have any new exposure within three months from your testing ,then you are safe,you are not suffering from HIV infection,
no more hiv tests are warranted without any new exposure,
Human body can experience lot of symptoms but all not due to HIV,please check with your for correct diagnosis for your problems,
I wish you for your good health
Take care
You've conclusively ruled out HIV multiple times with multiple negative tests. Therefore clearly HIV is not your problem. You need to seek other reasons for your problem.