I Have An Open Wound About One Quarter Inch In

I have an open wound about one quarter inch in diameter on my fore arm. I had a cancer removed. It's winter so I wear long sleeve shirts. The wound keeps filling with clear liquid. I'm afraid not to keep it covered but when I take the dressing off it seems to pull the top off and it fills with clear liquid almost immediately
Do continue to keep it covered so my sleeves don't irritate it?
It's been over three weeks.