Yes, you can amend your return and change your responses for your foreign earned income and deductions/credits. The only way to make changes to your original return is to file an amended tax return form 1040X reporting the changes.
Be sure you wait until your refund or payment due has cleared your account; before amending. As you start to amend, the tax estimator will go to $0 and then you'll enter your changes. Your amended return doesn't change your original return filed and instead will only reflect the corrections you make.
To amend your return, select 2016 and the type of software you used (online or desktop) and follow the instructions that result: https://ttlc.intuit.com/replies/3288565