That could easily be it - I get achey more now than ever, and put it down to the fact I have less fat cushioning me... my knee has really started hurting when I put weight on it - and turns out I've got a tracking problem in my first knee joint.
I too get some chest (ribs etc, rather than breating etc) pain, back pain, and I think it's posture - haven't started properly exercising yet - start on Saturday, so hoping building up some muscles will help... I do feel a bit weak and woeful sometimes, and have no strength.
When I get really sore, I just tell myself it is my body shrinking and it makes it so much more bearable!!
A x