Black box where the pens should be


I’ve just installed the program and bought the student version, now,

The pen that it sets to when you open the program works just fine, but when i want to choose another pen, it just says the name and it has a black box over it. Now, that wouldn’t bother me so much if the pens actually worked. When i click on one of those pens, it draws black pixels? And after i let go of the pen, it just puts all the pixels together and makes one huge black box. Please help.