Problems With Testicles ( NEED HELP )

So i don't really know if this is the right place to ask this but im 16 and i had ab undescended testicke surgery when i was little. throughout the start of puberty only my left testicle would grow and i thought that my right one would eventually but its been about a year now and am very worried. i don't know if theres anything i can do maybe it was ruined during surgery or something just wanting some medical advice and im going to try see a doctor soon but is there anything i can do or will it grow later in life or something? also having symptoms if low testosterone. any help would be appreciated or anyone with knowledge about this stuff. cheers