It's one of the most common words in the language so we're a bit sloppy with it. The ch has never mirrored pronunciation though, it could just as well have been written with ck from the start. Or k.
To say it correctly it's more like "ock" for an English speaker. But as previously mentioned it's common to shorten it to just a short o (all Swedish vowels have one short and one long sound).
When I hear "och" it kind of makes an oi-k sound to it. Would that be proper or how is it more properly pronounced?
It's just a short O or short Å, the -ch /k/ is usually silent unless the word stands alone or is emphasized.
The voice reads flicka as two different parts: flick+a. Are both syllables stressed?