The foundation of your music needs to be firm to be able to develop into a balanced musician / guitar player. If you are like me, you'll still want to play guitar in 20 years and will be eternally fascinated by the potential of the guitar and other instruments that the guitar will no doubt morph into.
What I‘ve noticed is that many self taught guitarists don’t see the pattern of notesas they move up the fretboard, “ABCDEFG”. Maybe the confusion came about because of a misunderstanding about sharps and flats and / or a music teacher told them, “Every good boy deserves fruit”, no wonder music students are confused. I was discussing this issue with my good friend the guitar great (the late) Ike Isaacs about 25 years ago, and we both decided that it should be outlawed as it is quite nonsensical and is really a hindrance to the learning process.
To put the following statement simply:
a Sharp is ONE NOTE HIGHER,up one fret on the guitar
a Flat is ONE NOTE LOWER, one fret down the neck closer to the tuning pegs.