Pregnant on birth control or just messed up cycle?

Brittany

So last month my dog ate my bc and I just thought I’d start over on a new pack. Now this whole week of my third week of pills I wake up nauseated every morning and today and yesterday I have had brownish discharge with light cramps and headaches. I’m a little concerned but I’m also thinking it’s just a mess up on my cycle for not having one last month.