Weight loss and breast feeding

Is anyone else losing a ridiculous amount of weight while breast feeding ? I’m down 18 pounds from my pre-pregnancy weight and baby is almost 16 weeks.

I’ve also been eating clean for the most part , I’ll cheat on Sundays and eat whatever I want that day and I try and walk 30 minutes each day w the stroller but I have done this before and have never been able to lose weight so I’m thinking it’s the breast feeding .

My other question is will I gain it back after I stop breastfeeding lol . Id like to stay this weight . Was 160 now 142 and 5 feet 3 inches .