Blood when I use the bathroom

I am a 23 year old male and in the past few months sometimes when I go to use the bathroom I have blood that comes from my butt.  There are small chunks of red in the toilet that turn the water in the bowl red and when I wipe it is all red.  This stays for a couple days and then eventually goes away.  I am in college and drink a couple of times a week.  I also had food poisoning a week ago and had liquid bowel movements that were brown and painful for 2 days so I don't know if that has anything to do with it.  I don't know if I should just let it go away or go to a doctor or what it could possibly.  Any help would be appreciated.  Thanks.

[PrettyKiity808]

Stop drinking alcohol until you see a GI specialist and at least find out whats going on. You could have an ulcer with occasional bleeding inside. Just a suggestion.