Hugs! He did gain, just not too impressively yet. More frequent weighing (every 5-7 days) will help you get a better idea of what's going on. My ds3 was slow to gain, much more so than my first two sons. Try breast compression while he nurses to squeeze more milk into him. Consult a LC if you can. Is he a sleepy nurser? You may just need to bother him a bit to keep him actively sucking and swallowing longer.
Ann, Mommy to 3 beautiful, boisterous boys:
Liam - 6 1/2, Emmett - 4, almost 5
and Callan - 22 months