Ive got a painless tender movable lump under my chin the size of a pea/ half a thumb for a year. gp touched it and told me its fine but wanted to make sure. before it appeared there was pain under my chin and that was 10 days after my covid quarant?

The space under your chin is called the submental area and is a typical place for small lymph nodes. These can persist for months and months. If not red, tender and the lump moves under the skin, this is likely a normal phenomenon. A doctor who examined you would be in the best position to judge.

You may feel the nodes/lump every couple of weeks, if any of the lymph glands doubles in size, becomes painful, ulcerates, or other nodes become enlarged, or you develop fever, or lose weight, you should see a doctor. Wish you good health!