Could a hydrocele operation make my penis grow a little bit?

Not usually. Not unless the hydrocele was so large that it was "burying" your penis. If it is now gone your penis may appear larger but in reality it is not. Patricio gargollo, md pediatric urology, dallas texas.
No. Overall lenght of penis will not change, but functional length can increase if hydrocele pushes scrotum up along base of penis.