Stick with it!
I took up aikido more or less because I have a lower back injury. The daily exercises I'm supposed to do to alleviate it are almost identical to the warm up exercises at the dojo I attend - just very boring when on your own. Aikido puts it into a much better context, and I actually feel more inclined to do them.
Just make sure you warm up fully - I'm out of circulation at the moment due to a knee ligament injury which I can only describe as my own stupid fault....