Positive test Turned Negative?

Marissa

I’m currently on Nexplanon but towards the ends of its life and planned on getting it removed next week.

I’m 13 days late which has never happened, nipples incredible sore and I’ve been extremely tired all the time but didn’t think much of it.

Took a test I had and it was positive for about 30 seconds before fading to negative.

I have no idea what this means. Husband and I plan on going to the store for more soon.