Lower back n one leg pain. Sometime.

I am 42 yes HT 5.4,wt 95 almost may be ,I have severe back pain left sacrum side n whole lateral side pain having lots of previous inj prick swelling on my buttocks which always painful since so many yrs but recently worst can't sleep also can't digest much pain killers becoz gastritis I will take only Calpol with ppi it mainly started after my pregnancy in 2007n one time fall in 2010 n trauma to coccyx fracture that time ..my wt also increased but inj pricks sweeling n sacrum side pain worded now n refereeing pain to left leg whole spe lateral side one perticular line looks like becomes hard vein / muscle feel hard on that line n it's painful also plz guide me what should I do ..numbness on lateral side tingling also sometime ..thanks I am always applying oint spray for pain and hot fomentation but not much relief ..if I will stand walk long time it become more worst pain ..plz plz guide me what should I do immediately for pain can't take aceclofenac n all so taking only Calpol.thank