Very rarely have pain in Achilles when walking too much in wrong shoes, so is surgery needed?

Probably not. If this is an isolated occurrence that resolves after wearing of shoes that don't bother you or cause symptoms you probably don't need surgery at this time. Physical therapy will likely help teach you techniques to alleviate your acute symptoms.
No. If you rarely have pain, switch to a proper fitting shoe and do achilles stretching exercises, use an ice pack to the back of your heel 20-30 minutes twice a day to reduce pain & swelling.