The lump may be a ganglion pressing on nerves, but you do need to see your doctor to look at it and give you the correct diagnosis and any appropriate treatment.
With regards to your stools, make an urgent appointment to see your doctor about this. It is difficult to say if it has any connection to the lump, but you do need urgent medical attention. Don't wait any longer as the symptoms you present with regard to your stools can be very serious. An early diagnosis is imperative.
you should go to your doctor now. this could be very serious. and it may not be. but you need to find out what is going on. mandy876