Some women do not work well with progestins.
Short periods and spotting are often a direct results of progesterone levels that are too low.
Estrogen dominance probably a factor in the lump. Estrogen needs to be balanced with progesterone.
She can try adding OTC 2% progesterone cream, but problems may persist.
Oral BC inhibits the HPOA, then the ovaries are lest active, which means less T. And her progesterone production is then also low. So she effectively replaces progesterone with progestins.
Note that oral estrogens have a first liver effect, and the E peaks seen by the liver are high, SHBG increases and FT goes down.
Blood work is a problem as levels change vastly over her cycle. And some women have much different levels.