Paid college in 2017. School starts in 2018. 1098T says I'm not part time, but I have 7 credits. Want The American Opportunity credit. Will this apply in 2018 taxes?

Paid college, books, and laptop in 2017. School starts in 2018. 1098T says I'm not part time, but I have 7 credits which is part-time. Want to take advantage of The American Opportunity credit. I emailed my school which said "Your semester 2018 is including from January-March.  This is your first semester that you have signed up for in 2017 year." Not sure what that means.  Will I receive AOC in my 2018 taxes and not in my 2017 taxes? Don't want to miss out.