Weight loss/no weight gain during pregnancy

So I will start by saying that I am 5’3 and about 165 lbs. I know that I’m not super big but I am about 25 lbs overweight. I just found out that I am pregnant with baby #3 and I mostly live pretty sedentary life. I am so concerned about gaining a lot of weight with this pregnancy cause I put on about 20lbs for both of my previous pregnancies, however, I started at 116 lbs with the first and 135 lbs with the second. Considering that I am already over weight, do you think it would be possible to at least maintain my weight now(if not lose a few pounds). If I pick up walking everyday and healthier meals? I know I shouldn’t suddenly start working out like crazy since my body isn’t used to it.