I didn't know I need a root canal, but when I found out I did go get a root canal. The gum on top of the root canal that I got done it was red and got a white spot like a ball. When I pressed or touched it feels tender. I was on antibiotic. I hope it to heal, but now I think it getting worst. 3 months after root canal, the redness is spreading and feeling tender. What is wrong? Is this an infection that is caused during the root canal procedure?