Age is definitely going against you. The thing that gets you as you get older is recovery time. Your body needs more time to recover between strenuous exercise bouts and/or injuries. Its a very gradual decline, so its hard to notice. From your message its sounds like you are working yourself very hard on an almost daily basis. At 22, no problem. At 33 it can leave you vulnerable to injury. Not allowing enough rest means your muscles and connective tiisue haven't had time to recover from their last use so they are not a 100%. These make then more prone to injury.
Try taking 36-48 hours off between strenuous bouts of execise, longer if you know you have an intense period coming up. If I know I have 2-3 days of back-to-back tennis coming up, I typically don't do anything for 4-5 days prior other than some light aerobics and stretching. That way all my body's resources are recovered and ready for the stress. This has really helped me as I've gotten older.
Drop me and email if you want to discuss more.