50% = average for his age so don't feel bad about that! I bet he is really active which is what gets them to burn all that fat. I'm sure he is doing great!
DS was in the 96th percentile all the way up until 6 months, then he dropped to the 75th, now he's in the 65th. Dr said it was more important that he is height/weight proportionate than what the percentile is at this stage. It is weird though because there are some pants that he didn't fit into and now they fit him again cause his belly is so much smaller! I started digging out all his old pants to see if they fit!
That is normal at that age. Babies are starting to hit the spot where they're going to actually be for life. DD started out in the 90th %ile and is now in the 25th%. And I know that you probably didn't mean it this way, but saying that you "feel like you failed a test" is kind of insulting to moms of smaller babies. There is nothing wrong with having a smaller kid (or a bigger kid or taller, shorter, whatever), as long as they are healthy.
Re: dropped from 75% to 50% in weight :(
thats not a bad thing...
Also, as they get taller it changes i believe
50% = average for his age so don't feel bad about that! I bet he is really active which is what gets them to burn all that fat. I'm sure he is doing great!