---I THINK MSM is supposed to help in increasing the growing time of your strands (so, you'll have less shedding). I've been having success with it so far.
---The b-vitamins inositol and choline are supposed to help with shedding also.
I stopped taking birth control pills a while ago, and I waited for the shedding to start 3-4 months later because of the hormonal changes, but so far, I've had no problems.
I think it would be helpful to increase the amount of essential fatty acids (omega 3 and omega 6) you're taking also because these nourish the scalp (Evening Primrose and Flax seed oil (or fish oil).
Good luck and try not to worry so much. It is normal to lose 50-100 strands a day. If you have long hair, 100 strands can look like a lot when balled up, so you might not have a problem.