I hope its muscle gain not weight

I just weighed myself and was 50.2Kg of weight 2 months ago and now I am 53KG of weight i hope it's from strength training and its muscle.. well I do feel stronger and happier then I was before...I did not eat much food in the past too but I am eating more because I used to feel low on energy all the time! But I am getting a bit of a belly again 😅