Not diagnosing you in any way here of course but I was going to suggest that you speak to your doctor about maybe having fibro. I have APS and have done for oh so many years now, having had SLE for over 30 years. I started to get real bad muscle problems and tender to the touch areas a couple of years ago only though, and this was later diagnosed as fibro.
Unfortunately, a number of lupus patients also go on to develop fibro as a secondary condition. Of course many people develop fibro as a primary conditon too, so it is really worth looking into. It might not be this but could you make an appointment with your doctor and ask him to check out the normal tender spots associated with fibro? Only a doctor will be able to give you a definitive diagnosis.
Looking forward to hearing how you go on with this.