Diarrhea And Constipation? Helpppppp

Hello everyone..I am not quite sure what's wrong with me. For a while now i've been having strange bathroom problems. I'm 15 years old. I seem to have to go poo all the time, even right after I go. My poo is like diarrhea, usually it comes out in very small pieces and is very hard to push out and i'm left with pieces just sitting there at the base of my rectum (i can feel it). It's hard to explain, but I feel like i'm at risk of crapping my pants ( ) all the time (and most of the time I am). This has been going on for approx. A month and a half (or longer). It is extremely uncomfortable and often painful when I do go..I'm seeing a doctor about it on wednesday but i'd like to know some information about what this could be beforehand.


Thanks!