I don't know your overall health etc., however, I don't think it's anything "serious" but as you know, you need to have this checked out. There are too many thing it could be to even begin to narrow this down is impossible. It may be hemorrhoid related. It's good that it's not blood flowing from the rectum area. Just a bit concerning since it's been a few weeks. Most common you may be looking at is an infection, which may be causing inflammation etc. (just because of the mucus)
But don't panic, generally we panic, just to find out in the end, it was for nothing serious. I am glad you will be getting check out.
As I stated in the first reply, if you can get a mirror, and see if you see anything around the anal area, this can help give you some ideas as well.
Here is a site on hemorrhoids as well, which may help.
read here
read here
Hope this helps Hun