A large blood clot developed after my gingivectomy. What should I do? Should I remove it?

Large blood clot. No! Don't remove it as it may induce more bleeding. "Large" to you may still be within normal limits. Call your dentist for advice. He/she may or may not want to see you to evaluate it in person.

Related Questions

Is it normal to have a blood clot the size of my tooth after a gingivectomy? I tried to rinse it out but it's really thick and stuck to my tooth.

How long has it been. While it is normal to have some clotting and bleeding after simple gingivectomy, the size you are describing is a bit bigger then usual. If it is no longer bleeding and isn't too tender (meaning it's been a few days since procedure) you can try to brush it off. Read more...
It is not normal. Go back to your dentist/surgeon for post-op appointment and management if needed. Read more...