I completely understand what you are going through, I had a lump on the bottom of my jaw a few weeks ago that had me worried. It ended up being a lymph node that was a bit swollen, don't worry...you should go to your doctor and have him take a look at it. I'm sure it's just swelling from the infection and the removal of the molar. Hang in there, I'm sure everything is fine. Best of luck!!!
Old line oral surgeons, usually the ones most recommended by dentists and the people dentists get their implants done, recommend 3 months for an extraction to heal. They can take a very long time sometimes. So it could just be that it hasn't had time to heal yet.