pregnant again???

Little back story.

Hubby and I have a 17 month old, before getting pregnant with her I was on the combination pill and got off it for 4 months and bam we were pregnant. Now trying to conceive our second and last I've been on the mini pill til 4 months ago going on 5. I still breastfeed but have had a regular cycle since I stopped my mini pill we had a chemical pregnancy Nov 2017 and now here we are Jan 2018 and I'm cramping 12 days before my cycle.... Could this be implantation? Attached pics of dec and jan cycles in three fertility apps. For reference.