I am breastfeeding a 8.5 months baby and my period wasn’t regular my cycle may take 38 to 40 then I found that i am pregnant at day 43 of my cycle

The question that i took multivitamins during breastfeeding including vitamin A I know that vitamin A is harmful to the unborn baby at the beginning of pregnancy so i stopped it when I knew that pregnant but did anyone has same experience and know later that the vitamin won’t hurt the baby ?