seems really common, and especially early on. your brain/mind processing stuff. not to worry; i've had some and am years sober
if you think it relates to "real" stuff that happened/you did when drinking, you can give thought to tackling that when you're feeling solid in sobriety.
just keep going, and you'll have a few more dreams and wake freaked out and find you can be okay just the same.
and also, it's good to remind ourselves we tend (well, i do!) to pay more attention to those nightmarish dreams than the butterfly and sunshine ones as far as possible significance.