Possibly pregnant less than 8 weeks postpartum...

I'm seriously afraid I might be pregnant again & I had a csection almost 8 weeks ago.. We used protection at all times but know that's not 100%... I know it's best to wait 12-18 months before getting pregnant no matter how the baby came out. Just a little note, I had no complications what so ever during surgery or during the healing process. Haven't had my period yet & not fully breastfeeding. I quit spotting about 2 weeks ago & it started a few days ago that was pinkish brown mixed with mucus and cramps, I'm hoping it's just a sign my period will be coming back soon! I'm not asking if you ladies think I'm pregnant cause I know the only way to tell is to test or go to the dr. I'm just wondering if any of you ladies or someone you know got pregnant so soon after a csection?