Blood in stools. Metronidazole.

Hi!there ....basically it started on 25th of last month I used to get little bit of blood in the loo...after few days I started to feel pain in the anal area while trying to loo... as if thorns came out in that area...it's been really difficult to go to the loo because of pain and there's blood...there was always a sensation of gng to loo...if I go to bathrum even if I try hard there will small bits of loo that's it...sometimes only the flow of blood ,but i never felt pain by that time...after few days there was no blood but only mild pain..again from yesterday it started to bleed again like loose motions ..now the pain not severe but there is a pain..there is an urge to go to the looo..after trying harder n harder same old thing bits of loo...today I went atleast 15times ..still I feel like gng but of no use ,since evng I got mucus like jelly thing of yellow and then white now...what is this condition?should I take RIFAXIMIN,METRONIDAZOLE ...prescribe tabs for pain and cure please