I have pain in my left rist when doing pushups. can i reverse that?

All in the mechanics: It is very likely reversible. Wrist pain when weight bearing can be as simple as muscular imbalance or as serious as a ligament tear or stress fracture. Do not push through pain. If it doesn't improve with ice (10minutes a few times/day) and range of motion exercises, get it checked out by a physician.

Wrist position: Do not do pushups with wrist in extended position . Use a neutral position by making a fist and doing pushups with the fist padded. Extended position puts extra force across the carpal bones and TFCC causing pain.