Third trimester weight

How much weight have you been gaining in the third trimester? In the second trimester I gained a lot. Like 6 to 8 pounds a month and my doctor told me I was gaining too much. Gained about 27 for whole pregnancy so far. I haven't changed my eating at all since then but when I went in today I only gained two pounds this month. (I missed an appointment so it had been a month since I got weighed). Should I be concerned about not gaining weight in the third trimester? My doctor didn't say anything. I'm 33 weeks now.