Pregnancy Weight Gain!!?

So this might be weird, idk lol. 
But I'm 5'6 and 140. 
I hardly ever feel comfortable in my body and I just found out I'm pregnant.
I'm not sure if that's a good weight for me and I'm so scared to gain a lot! 
I really wish I could have lost weight before hand but as long as I stay healthy and active through my pregnancy I'm sure I'll feel better about myself. 
But what would you say is a healthy weight gain through pregnancy?