Said with a rising tail, a verb followed by 말아 asks yourself whether to do the thing or not: should I ring him or not, should I eat this or not, do I quit or keep going. It is dithering out loud rather than a real question to anyone. The same verb is the one used for telling someone not to do something, which is what the line about not being shy is doing. Some of the printed lines only sound similar and are other verbs entirely.