The annoying thing about injuries in my experience is knowing that if only one had started taking it a bit easyer a bit sooner THERE WOULD BE NO INJURY. I think if you have any soreness that lasts more than a couple of session, or is becoming worse over a few sessions, then its time to think about what you are doing and how you can change it to give the injured area a bit of a change or a rest. Just a couple of weeks doing something different and it will prob go away and bingo, you can carry on.
Pretending it will go away by itself usually leads to INJURY.