Frustrated

So I received my first period after baby on August 4th and my husband and I had sex pretty much all month, didn’t want to miss a possible time while not testing for ovulation. Last Tuesday I had spotting in my cm when I wiped, so I thought okay maybe that’s implantation bleeding. I have been nauseous, cramping, tender nipples(which you can really tell when baby is latched; never been a problem except for mid month last month before I got my period back) I am also super bloated, and pretty constipated the past two days, which normally I’m super regular especially around period time. And I’m thinking I have a chance, but I wake up today and I’m cramping, and when I am on my period I get this weird thing where my butt almost feels numb and I’ve had that today. So I’m pretty sure I’m going to start my period very very soon. I just really really don’t want to stop breastfeeding to get pregnant again. I did it with my first and I felt so guilty like I was somehow putting my wants before his needs.( I stopped at a year so he was okay but still)