How long after a hernia op can i start working?

I'm 24 and 19st if that makes any difference, i play rugby and weight lift, whilst at the gym early this year i got an inguinal hernia on my left side and after an ultrasound they found another on my right side! i had open surgery on the 23rd May for both, realistically, when can i start working, (i'm a police officer.) and when can i start lifting any kind of weight, i've been told walking is the ONLY thing i'm allowed to do and i haven't stopped, it's been a month so far and i feel ready to run a mile but wont risk it however i had planned a camping trip across the Brecon Beacons in Wales next week, (5 wks after op) and wondered if i should. Any help or suggestions would be great thank you very much.