Swelling

Hey so I'm 21 weeks tomorrow, and for about 2 weeks I've been swelling up. The first time it was just my knees I was sick all the next day had no energy and could hardly walk, i went to the doctors and they said my legs can't handle the extra weight it needs to carry, when she examined my legs she was looking for vains sticking out (there was none at the time) all week I've been getting sent home from work early as I can just about walk my feet have also started to swell and walking is becoming a task, last night my face also joined in on the swelling and my we noticed vains out on the back of my legs, I've also been feeling sick again especially around food, everyone tells me swelling isn't normal until 7 months. Should I go back to the doctors? Sorry about the long read but just worried