Depo Provera

Ika 6 weeks & 2 days ko n ngayon after manganak. I went to health center for family planning and prior to giving birth they advised me to have Depo shots on the 6th weeks postpartum(1st time sana to use contraceptives) . Kaya lang hnd nila nasabi sakn na bawal pala ang may sexual contact since the time I gave birth up to present for injection. Napagusapan nmn to ng husband ko dahil 3months n kming walang sexual contact nakiusap sya na baka pde na. Since exclusive breast feeding nmn ako I thought completely protected nmn kmi lalo na at magwithdrawal nmn. Nabasa ko kasi it's a form of contraceptives as well(LAM). Pero sabi sa health center hnd daw un assurance na hnd ako magbubuntis ult kht exclusive BF. nagworry tuloy ako at nag PT agad immediately though it's negative naman still hnd pa kasi ako ngkakamenstruation kaya mejo anxious ako. Na confuse ako sa LAM method. Saka na daw tlga ako injectionan pag nag return n ang menstruation ko. Please enlighten me. Malaki ba tlga ang chance magbuntis kaht exclusive breastfeeding? Thank you