Mazal tov on the birth of your daughter!
A hefsek taharah need not be completely clear. Even some browns may be acceptable. In general, in hilchot niddah, yellow discharge without any reddish tint is treated the same as clear discharge and should not interfere with becoming or remaining tehorah.
Please note that pospartum bleeding does typically come and go in waves, and fifty percent of women do have bleeding for over a month. So do not be surprised or alarmed if bleeding starts up again. But you should also not hesitate to attempt a hefsek taharah and to ask a rav to evaluate bedikot if you have questions about them.