HEALTH PROFESSIONALS PLEASE REPLY

On Tuesday (yesterday) I woke up to a painful lump on the side of my right breast near my armpit, on top of the lump looks like a head but I tried to burst it thought it was a pimple only a small amount of liquid came out. I'm worried !!!! I made an appointment with my Gyno a week ago for next Thursday to check my fertility for me and my fiancé have been trying for over a year. Should I bring it up in that appointment or is this alerting making a sooner appointment for the lump???!!!! I'm terrified please don't let it be cancer. I need some help in detecting if this is a cyst or something more serious.