To diagnose a problem with the port, try using a different battery and cord for a while. Damaged Power Cord. The power cord is a wire inside a plastic sheath, and the wire can break with or without damage to the sheath. If the power goes on and off as the cord is moved or bent, the wire is likely broken.
You can work out if you're sore. Don't exercise the same muscle groups that are hurting. Do legs one day and exercise your upper body the next. By doing so, you'll still be able to get exercise and allow your lower body to recover and rebuild.
Basically whenever you feel like your body is getting used to the workout, and it is becoming more difficult to get that sore feeling, you need to switch it up. Keep your body guessing. most people I know say that you should stick to a routine until you start to plateau.