I have a painless pea sized lump just under the skin near my abs. What could it be?

Cyst, lipoma. This could be cyst, a lipoma or benign lesion. It could represent another type of growth and from the des ription alone it is impossible to give a definitive answer. It is best ot see a doctor for proper diansosis and possible removal .
Need to examine. It is not feasible to provide a meaningful opinion without examining you. You may wish to watch and wait. If the the "lump" more than doubles in size, bleeds, ulcerates, you get fever or lose weight, see a doctor.
Have a healthy diet, exercise, drink plenty of water, have safe sex, and get HPV vaccine. Wish you good health!