you can purchase 'udder balm' or another similar prodcut. and it will smooth out the area, so you can pinpoint the bumps, and see if they are lumps under the skin, or raised.
i have a 3 year old female goat, and she has some also, i used the udder balm to soothe the chapped areas, and in a week or so the bumps got smaller.
Gentle message and warm compresses would help. The udders may need infusion with antibiotics, and she may need oral or injectable antibiotics. If she is older it could also be mammary carcinoma, unfortunately.