Why would i of been prescribed zoloft (sertraline) if serotonin makes skin burning worse ? would amitriptyline help instead ?

They didn't know: Amitriptyline also has a long, long list of possible side effects. Not everyone suffers them, certainly not all of them but they are possible. Same w/ your Zoloft (sertraline). It's trial and error and none are 100% free of bad side effects. If you cam minimize use - good! CBT therapy can help you do that. Don't try to self- Rx - it takes training and you're sensitive on top of that.