It is very hard to say what the lumps are without seeing them.
According to the data you reported, you might be experiencing a genital infection (lumps, burning when urinating) or clogged excretory ducts that might have caused certain of the local mucosal glands to inflame and swell (lumps, bigger after sex).


You might want to visit your gynecologist and have a urine culture and vaginal swab for the genital infection; and vaginal pelvic exam for the possible inflamed mucosal glands.


The treatment might include antibiotics for infection or local anti-inflammatory drugs for inflamed glands.