I used to have basically the same truck you have: 2012 F150 Ecoboost with 3.55 gears, although mine was the long wheel base (Crew Cab with the 6.5 foot bed). I used it to tow my enclosed car trailer that is 29 feet overall length, around 7,500 pounds. I now have an F250 diesel that definitely tows the trailer better, but my F150 pulled it just fine.
You won't have any problems with power just expect to take a big hit in MPG when towing. That Ecoboost engine is pretty awesome. I used to get 20+ mpg on the highway when I wasn't towing.
Also make sure you're properly balanced and use a WDH. On my F150, I installed a Roadmaster Active Suspension, which helped stiffen and plant the rear end. Took 2 hours to install.
Personally, even if you're right at or over the 'paper' limit, I think you'll be fine having personal experience owning the same truck towing a similar load.