Really late period

Rachel • Di/di twin boys and one on the way👦🏻👦🏼👶🏼

When I was four months pp, my dr prescribed me birth control but it decreased my milk supply so I only took it for one month and my period never came. It’s been six months since then and I still haven’t had my period. Should I be concerned and call my doctor? I’m bf so I haven’t been too concerned, but that’s a long time so idk.