were people afraid of doctors in the mediaval times?

There was cause to distrust them, yes. u/pettylarceny goes into further detail on that matter here.

as much as i know doctors werent to good at their job

Depends on what you're looking at. Common Knowledge, as ever, is off the mark with its views of Medieval medicine, as we'll see:

• u/BedsideRounds has a non-exhaustive list of Stuff That Worked;
• u/BRIStoneman presents Bald's Leechbook, a medical text from the 9th Century;

Bonus: u/BRIStoneman does link to it in their earlier answer, but for the convenience of anyone wanting to read the original, Bald's Leechbook is available in all its digitised glory here.

And as always, further contributions are more than welcome from anyone with knowledge! Medieval medicine always gets a bad rap in Common Knowledge.