Breastfeeding frustration

So I went to my pharmacy and asked if there was a supplement I could take to help increase my milk production. The pharmacist said vitamon b-6. I have taken it for 2 days and noticed that I havent been able to satisfy my son with just breastmilk. I pumped several times today and my milk has decreased immensely in the last 2 days....I just looked it up for myself and they use b-6 to dry up milk supply. I am so frustrated! Here I am doing everything in my power to increase and now I am fighting against myself.