Dental abscess over root canal

Hi all. I previously had a root canal done on the very last tooth on my upper right side about 6 years ago. I put in a crown on that tooth about 4 years ago. I've always had pain there and my dentists have always told me that it is just pressure because my sinuses are located close to the tooth. I recently went back to the dentist who noticed an abscess. I have an endo appointment scheduled in 2 week's time. The abscess really grew and popped tonight. I could taste alot of blood, though not pus. Is it worth going to the ER or just wait for my appointment at the endo?

Thanks for any advice.