Sciatica problem. Future tertement also!

Actually I am suffering lower lumb pani to tie part pain for 3months... I doing everyday physiotherapy from past 20days... First 4 days i get pani from my lower lumb to side of tie part pain... After that past 4 days back i get pain from middle of body which I show you in pic with bandes pasted for pain... At that place ther is (nuts) like blood clots if  i touch on that place i getting pain a lot and my physiotherapist told it's an sciatica pani... But i can't trust him... So plz let me know which pain and future tertement also thanks Now my syntems I geting  pani from back side of lower lumb to tie and knee part to upto foot... Can able to walk Some time from hip to front tie part beside our private part joint... Geting pain including that...