Eat to maintain and gained RAPIDLY?!

Hrl1993

So I decided I was just about happy with my weight and started eating to maintain (my stats WERE 5'4", 125-127 lbs). All this month, I had a net average of 1600 cals/day. I've been eating somewhat low carb, as well...not keto level, but all "good" carbs and like 35-40% of cals from carbs a dayI did have a few cheat days, but always had a deficit on other days to account for those extra calories throughout the week. I hadn't weighed myself all month b/c I didn't have a scale, but got on the scale this morning...and weighed in at 137!!

I'm trying not to panic - hoping it's one of those weird "up" days - and I've been doing this for long enough to realize it doesn't really make sense for me to have gained 10 lbs. Then again, it would be weird to just be up 10 lbs in water/food weight, so I'm a little upset.

Should I be eating less to maintain? I'm so frustrated...I feel like I have to start all over!