New to boating, Should i be worried?

[StBalor]

Well i realized something yesterday. Maybe it was partially my fault the water was coming over the boat. The 1st 2 times i went out there were 4 of us. i figure weighing about 1000 lbs. Water was choppy and all 4 of us fishing off of back of the boat.
Went out on the potomac river yesterday with 3 of us water was calm and we spread out on the boat a bit. Not a drop of water came ove the transom area. in fact no water came in boat at all.
Was this a rookie mistake by all 4 of us fishing from back of boat that caused the water to come over the transom?