What’s the chances?

I had the depo injection January 27th first one since I decided to go back onto it and I’ve been fine since having it (had it few times over the years never had a problem) I know spotting can be common in the first few months of using this, the nurse said to use protection or abstain for the first 7 days after getting it. We used protection during this week now on day 7 we didn’t, but thought it would be okay.. this was Feb 3rd. Now this morning I’m cramping ever so slightly and I have brown spotting only when I wipe after the toilet, what’s the chances we’ve messed up and I’ve caught pregnant or it’s just a side effect? 😬

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