Really there is no big problem here,,,your a photographer who wants to improve,,the fact that people want to pay you shows that you are indeed getting there,
As for price,,,what would you be comfortable with ?? dont rip anybody(including YOU) off and enjoy the experience.
All i would urge is DONT undersell yourself,,,,i have to smile,,years ago i fell into the trap of working for next to nothing on the Gig circuit,,,
ended up doing nothing rather than work for free,,,,
Good luck with it