bad leg pain

[pulse90]

hi, i have had this pain on and off for a couple of weeks. it is in the top inside area of my right thigh, (seems to be right inside the leg). it happens in spurts or roughly every few minutes when it is at it's worst. then disappears perhaps for hours or sometimes a few days, then back with a bang!! and a very sharp stabbing pain.
i am in my early 40's, slim and fairly active. i do not like troubling the doctor unless i have no choice. i had a fear though that it may be a blockage of some sort, or could it be the start of varicose veins? maybe i'm panicking a bit prematurely? could someone please help with any advice?
many thanks

[redcrx]

if you dont want to trouble your GP then how about calling NHS direct for advice.

If you have a fear it may be a blockage then why would you think youd be troubling your doctor?