i have the exact same problems. it is more than likely sciatica.... which is horrible. im 25, and i have been heavy off and on all my life as well. I had two kids, and in this process i gained weight also.. im just over 270 at this point and 5foot 6in...so i could lose some weight, but i cant even walk a tenth of a mile without thinking im going to die... i break out in total sweat, everything ceases up, bad headache comes over me, and i just feel like im broken....this is a problem i have in my everyday life....i take naproxin 800s and im fine, so its nerve pain, the sciatic nerve is the biggest nerve in the body...