take some aloe gel, lavender oil and mineral oil and mix them together into a lotion. That will help the sunburn feel better and heal faster. If you have some vitamin E oil, add that into the mix. Should only take a day or 2 before the red turns to brown and you're back on the exercise wagon.
You might be able to get in a pool if you have access and do some water exercises. Also you should be able to do a recumbent bike. I would just keep it low key and not go full out if you do something like walking, which would have you swinging your arms and stuff.
You might even be able to do some basic balance exercises (yoga).
I want to exercise but...
