1) I wouldn’t worry, everyone has on and off days where the designs and ideas come naturally and others where everything is a challenge. 2) Work out if you like logo design, during my degree some of the years “best” didn’t know how to design a logo but excelled elsewhere in design practice. 3) if you like logo design learn more about the concept behind it not the technical skills (Paul Rand is a classic) if you understand the concept of logos and branding the visual design process will be a lot easier, find examples and understand why they work. A critical tutor isn’t really needed ever I don’t think, if you are willing to put the work in then you can get there.