Pregnant again?

So ladies I feel like this is impossible because me and my husband have been taking precautions but.... I'm having the same exact symptoms I had when I first got pregnant with my daughter. Lots of saliva, cramping, no appetite and constipation. Now I'm having nausea. I took two dollar store pregnancy tests and both came out clear negatives so what going on with me?! I haven't had a period since having my daughter and she is three months old. Me and my husband have also only had sex about 10 ish times since I've had her and I'm on the pill and he pulls out 😫