Already injured

Who knew playing guitar carried serious risk of injury? I didn't in case you're wondering. One of the reasons that I started playing this year instead of last year when I first got my guitar is that I injured my left arm lifting a heavy couch.
According to my family doctor my injury was like a tennis elbow and it would heal with rest and some specific exercises. I thought it was better but now it seems that my playing is causing trouble in the same area again.
I'm not sure it's in the exact same spot and I'm pretty sure that this time it is not a tennis elbow but at times it can be really uncomfortable.

I didn't mention this in my first post but I've started to take lessons as well because learning from a book isn't everything. I won't name my instructor here until I have his permission (which I may never get) because I do want to protect the innocent. For now we'll call him Agi (anonymous guitar instructor) and I can tell you that Agi is a pleasure to work with.

Anyways, back to the injury. I've googled for arm exercises for guitar players and even found some tips for preventing injuries but I can't say I feel I have a good answer to this problem. I've iced it after playing and that seems to really help but I don't know if I feel like icing my fore arm every time I play because I'm a wannabe rock star and not a wannabe major league pitcher.

Agi didn't really know what to do about this either. He is after all an instructor and not a physiotherapist. It's comforting to know he has not dealt with injuries too much because that means he probably teaches in a proper manner because I've read that proper posture etc. does help prevent injuries.

One thing I'm wondering about is if I should switch to an electric guitar. My acoustic is not as easy to play as an electric and I wonder if I'm not putting more strain on myself than I need to. Besides that I want to play electric anyway at some point because it will allow me to play through an amp with a headset so that I don't disturb the rest of the family with my feeble strumming. After all, how many people listen to poor renditions of "For he's a jolly good fellow", "Jingle bells", "When the Saints come marching in" and that sort of stuff for fun?
There are better tunes that I'm trying to master but those aren't really fit for public consumption either so an electric guitar might be the stone that kills two birds.

If anyone who reads this has a killer tip on how to solve my injury problem I'd be very grateful. You will be included in the thank yous on the sleeve of every album that I'm going to publish in my future rock career. You might also be able to become the fore arm fixer for the stars from then on and that can be pretty lucrative.