I can only carry small amounts of gold at a time but if I go to the 'General' area I have a lot of gold listed there. Is that normal? How can I get my gold when I need it?
This is normal. What you're looking at is your Statistics page. There are two entries there about gold, one for Gold Found and one for Most Gold Carried. These are all-time records that you've set, and include gold that you've spent and no longer have. It's just a bragging-rights number.
The gold in your inventory is all the gold you have.