TTC baby #1.

hello ladies, so me and my boyfriend are happily TTC for baby #1. I’ve never had irregular periods since I started my period when i was in 6th grade! I am now 21. I had gotten a depo shot of March2017. and didn’t get it again. (never got pregnant) started the pills in january2018 for 1 week they were giving me a headache everyday! which stopped my period for 3 months. then got a regular period for months April and may, and now i am 8 days late on period.. but tested negative on day 4 of being late.. Possible period is being irregular again?