I use a 3 month cycle birth control, and I would have conceived in the beginning of December 2017. I have been on birth control and missed a day or two at times. My last period was lighter than normal. I have kept on taking it because i have not suspected anything until I noticed i put on weight, have cramps, am very emotional, and have been spotting (although it is the week before my period). I bought 2 home tests that both came out negative but I am still concerned. I just am inquisitive because i’ve heard home tests can be incorrect after 12 weeks, whereas I would be 16. Thoughts?