#1
I have a problem when i play my bass when i am standing up, the weight just kills my shoulder is ther a way i can fix this or am i just a whimp.the bass is a squier affinty p bass its not that heavy when i carry it
#3
There are two reasons your shoulder hurts -

1, you probably aren't used to it. The more you play standing up the stronger your shoulder will get.

2, Your strap isn't wide enough. When I first got my Ray 35 I couldn't play standing up for more than 10 minutes because it was so heavy. I then bought a 3.5" strap instead of the 1.5" strap I was using and now I'm fine.
[Insert something clever here]
#4
How big is your strap? Wider straps will help distribute weight and make if a little easier on your shoulder. My Warwick weighs a lot, but with my 4" strap it isn't bad.
So that with good courage we say, “The Lord is my helper. I will not fear. What can man do to me?”

-Hebrews 13:6
#5
get a wider and more padded strap. (as has already been suggested)
Belief is a beautiful armour but makes for the heaviest sword.