[gassiss]

if your weight didn't change, most likely you were eating at maintenance. The fact that you have a surplus every now and then won't change your body composition. Consistency matters a lot with regards to human weight.

To add to what someone else said, you probably ate below your threshold to be able to maintain your weight. You can't guess this, the only way to get an accurate ESTIMATE on how much you actually ate in calories is to measure. Even pros over/under estimate what they eat in terms of calories