7 month old has stopped gaining weight

Looking for some comfort. My seven month old was born 9 lb 5 oz and gained 3 lbs a month for a while. At 5 months he was 24 lbs and has not gained an ounce sense. He was weighed at the doctors office at six months, and again today, and was exactly 24 lbs. 5 oz. five at the doctors and is exactly 24 lbs. 5 oz. still. He is breast-fed, and began solids around 5 1/2 months. He is not too keen on solids, and gets most of his nutrition from milk.  Is this common? My pediatrician did not seem concerned, but I do think that it is odd. Thank you!