I lost 3 kilos in one month

I used to be very slim but gained quite a lot of weight due to mental health. I decided it was too much, took a personnal trainer and started a strict diet. In one month i lost 3 kilos, 5% of body fat, 1,5 kilos of visceral fat and gained 2 kilos of muscle. When i got back home from the gym i took my clothes off and looked at my body in the mirror for 2 minutes, i was so proud and happy, it was so much efforts