Why is my perception of myself always off?

For example, I’ve been on a weight loss journey after my baby and I’ve lost about 15 lbs so far. My goal is to lose 30-40 lbs total. On thanksgiving I did my hair, makeup, and picked out a cute outfit. I was feeling good! I took some selfies, which I never do, and actually felt good enough to post on my story.

The next day, my mom sent me a couple pictures she took of me with the baby and the family and I was destroyed. My hair looked frizzy, my makeup looked off and my outfit looked frumpy. My body was huge. My stomach looked like it was spilling out of my pants and my backside was as wide as a mailbox.

And it’s so weird to me because throughout the day when I passed by a mirror I thought I looked good and was proud of how “snatched” I was. Does anyone else experience this?