Birth control

So I’m 6 pp after having my son. And I told my doctor I want the pills for birth control. She put on the 3 month pill where u will have a period 4 times a year. Well last night I started the pack like my doctor said. A hour past after taking the pill I felt like I took a sleeping pill. I was so tired I could not keep my eyes open at all. And when my husband woke me up to feed our son I felt dizzy and sick on my stomach. After feeding my son I put him down and I went back to sleep. No joke I could not wake my self up to feed my son. I never had this problem. I’m always up when it time to feed him or change his diaper. My husband had to get up and feed our son because I would not wake up. Well when I woke up this morning I was still sleepy. I went to go pick my up my son to change him and feed him I got so dizzy I about drop my son. Lucky I put him on the changing table before I pass out. Has anyone have this problem? Did u have to change ur birth control? I’m scared to take the birth control again because of that.