I made a pumpkin ale with home-made "caramel" before. The thing is that real caramel (from what I've discovered online) uses salt, butter, and cream. I didn't want these in my beer so I made a simple caramelized sugar in a small pan. I found it to be a bit difficult (no candy making experience) so I would recommend that you stir often to keep it from sticking too much, don't use too much water or it will take forever, don't let the heat get too high, and don't leave it unattended! Using some vanilla also added to the flavor perception of caramel from what I could tell. For more caramel flavor I've found that specialty grains (crystal malts) are the key. I know that doesn't help you because you're already done, but it's something to look at in the future. Additionally, you can add something like Torani sugar free caramel syrup.