I'm not sure what kind of help you are looking for. It's not clear that there's anything wrong with your tax return. There is certainly nothing unusual about the tax increasing because of excluded foreign income.
As I said earlier, we can't help you any further here because we can't see your tax returns. I'm a bit surprised that TurboTax support couldn't help you. They should have let you talk to a tax expert, and I believe they have the ability to look at your return with your permission. You might want to try calling again and ask specifically for a tax expert who is familiar with the foreign earned income exclusion.
If that doesn't work, you should probably visit a local tax professional, and bring copies of this year's and last year's tax returns.
