As far as I understand, you already have one unconfirmed transaction and you are trying to send another one or the you have an incoming unconfirmed transaction and you are trying to send it while it's still unconfirmed?

Either way, you just need to wait for that unconfirmed transaction to get atleast 1 confirmation before you can send your balance. That yellow exclamation is a sign that the source of your funds is still not confirmed on blockchain.