What is happening to my body? (nsfw)

One day in the last week I happened to forget to take my pill so the next day I just took the one from Tuesday on Wednesday and I’ve continued doing that since then, but two days after the day that I forgot to take the pill I noticed some spotting on my panties. It’s dark brown goeey sometimes thick looking-like discharge/blood coming out of my vagina. I’m not quite sure what is happening with me. The spotting has been going on for a little over a week now.

Oh and just now I read my manual script of how to take the pill and what to do if one day is missed. It says that the day I realise that I’ve missed one day I should take two at the same time and obviously I didn’t do that. So I’m wondering if I should maybe do that tomorrow and maybe this is the cause of the spotting.

I’m very confused as to whether I’m maybe pregnant or not (which doesn’t make much sense though considering that I’m experiencing spotting) and also my breast have grown like a lot in this past week. I’ve been on the pill since the beginning of the year and I’ve never ever missed a day.

Please help me in this crisis that I am. I’m left stressing on and on about it and don’t know what to do. My mind tells me I might be pregnant but thinking of it, it doesn’t make sense and I’m left confused.

Thank you in advance.