back again - anesthetic question

Afternoon all!
Im back again for some more advice - I was diagnosed with PCOS after i had my son in 2008. Periods have been up and down since then, but for about the last year Ive had one every 3 months. About 6 months ago, i had a bleed after intercourse. Then it happened again about a month later. Went to the doctors but they didnt seem overly concerned (last smear was 2013, had a colposcopy then as had mild dyskerosis, then had a hysteroscopy in 2014 as I was having irregular bleeds, they found and removed a polyp, no further follow up)
Last month I had 2 periods in 4 weeks, the second one was more brown colored blood for about 2 days then a full normal period. Ive recently been diagnosed with fibromyalgia, chairi malformation, syringomyelia, mild disc disease and cervical stenosis, im also waiting to be checked for hyper-mobility. The dcotor said none of these things would contribute to me having these bleeds.
Hes refered me back to the colposcopy clinic - now i know from past experience and my current symptoms of hot flashes, grumbling period pain, mood swings and the irregular bleeding that its likely theres another polyp - i had these symptoms before! Can i ask to have a general anesthetic? I know, there is no way am i going to be able to lie in that position for anything upto 30 minutes… all my conditions cause me widespread pain in my body, so laying in a chair that long is going to be nae on impossible for me. Has anyone had a colposcopy under anesthetic?