Fiesta Year 2014. - Power steering seems heavier to steer than usual - SLO76
Not sure what fluid level you checked as this era of Fiesta has an electric power steering system and not hydrolic so there's no fluid in it.
It's sadly quite a common failure on Fiestas for the EPAS column to go wrong which usually manifests itself in one or all four ways.
1. Heavy steering in both directions.
2. Intermittent loss of steering.
3. Complete loss of power steering.
4. Power steering light illuminating on the dash.
You need a competent auto electrician to check this out, it is safety related so don't delay. I'd try the main dealer first, even if your warranty is up I'd expect some goodwill if you've maintained a full dealer history and the car hasn't done a huge mileage but if they refuse to offer any then a quick google search should pull up other options. There are firms out there who repair them or offer refurbished systems.