How much did you gain during your twin pregnancy?

I am 31 weeks pregnant and at my last appointment I was 135. I started out at 110. So I have gained about 25 lbs so far. My doctor said its normal to gain between 35 and 50 with twins according to my small frame. (4'10 and 110 lbs) in the whole pregnancy. I don't want to sound selfish but I am terrified of gaining another 20 lbs and I have heard you pack it on in the end, and I'm reaching my last 6 weeks (c section at 37 my doctor doesn't wanna risk placental breakdown) anyways. I just wanted to know other women's experience and if you don't mind sharing. Thanks so much!