That's a lot of weight too lose - likely too much. Losing forty pounds in such a short amount of time doesn't really give your skin much chance to retract itself and maintain its elasticity. It's usually suggested that you lose 1-1.5 pounds per week if moderately overweight. Those who are bigger can lose more than that, but you have to be careful of saggy skin. If it sags now after losing forty pounds, you should probably slow the weight loss down to avoid drowning in your own skin at the end of your goal. I know that losing weight is important, but so are aesthetics for most. Make your choice wisely because I know many people with leftover skin flaps who wish they would've been more patient for their skin's sake.
If you are planning on losing 130 lbs, total, I'm guessing you are probably well over 350 to start with. You're dropping weight fairly quickly, keep in mind it is fairly common for people experiencing radical weight loss to plateau - it's virtually guaranteed. There are various strategies to break through plateaus, but generally time is your friend.
It is very easy to get discouraged when you plateau, but stay with it. I find it troublesome that a doctor didn't consider a 40-lb weight loss in less than two months concerning. That's almost 5 lbs a week, not generally recommended unless you are being closely monitored.