Gum swelling

Hi, I'm 29y.o. male, I have a semi soft swelling on my Left 1st molar tooth gum. It has sort of a pyramidal shape and ends with a small point that once in several days fills up with whitish fluid. I drain it and a little amount of tasteless whitish-clear fluid comes out, then swelling goes down for a while. I have had this problem for about 5 months, and it hasn't changed in size. It is painless and looks the same color as the gum except for the tip. The tip is the same size until it fills up with fluid and looks kind of whitish.
I had a root canal and a crown done on that molar tooth about 4 years ago. I'm planning on going to a dentist in a few days, but just wanted to see what it could be.
Thank you