chance of getting pregnant

Hi mommies out there! May tanong lang po ako pwede kaya akong mabuntis agad kahit 4 months pa lang baby ko? first baby ko po sya. Last sept 21 i had my first mens after giving birth last june. Then I had sex with my husband on October 17 then supposedly kahapon oct 21 sana ako ulit rereglahin pero wala hanggang ngayon. Exclusive breastfeed po ako pero worried ako baka maagang masundan si baby. Sana po moms masagot nyo ako. Salamat po.