Correct me if I'm wrong, I''ve been working on sentences such as: "Mwen gen yon maladi ki pran m" meaning "I fell sick"? Is the Creole right?

Yes it's right.
You may also use verbs other than pran. You probably already know that.

Mwen gen yon tèt fè mal ki pran m.
Mwen gen grip ki pran m.
Mwen gen yon grangou ki bare m.
Mwen gen yon pipi k kenbe m.
Mwen te gen yon lafyèv cho k tonbe sou mwen.

Eskize m. M toujou ap konplike bagay yo.  Se defo m :)

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