All musicians should learn music theory, that is the details of how music works. The 3 ways people learn music is by ear, by feel (muscle memory), and by brain. Obviously anyone will learn music more quickly if they use all 3 ways together. All of our students learn to read music and to understand scales, keys, and chords, to speak the language of music. But not all musicians need to read FROM music, that is, the primary way they are succeeding in making music is by reading dots on a staff. Many factors affect this issue, like the kind of music and the instrument you play. The voice, for example, is pretty thoroughly designed for use by anyone. Everybody sings "Happy Birthday" at the party, but almost no one who sang it knows the notes or the key it was sung in. All notes in the voice are made the same way, and for most people the notes are made "naturally". Instruments where all the notes are played about the same way (piano, guitar, bass, strings, etc.) have a harder time keeping track of what notes are being played - because they all look alike. For the vocalist, guitarist, bassist, you should learn to read music and understand music, but you will only need to read FROM music if you A) like and want to do classical music, B) love jazz and/or progressive rock, and/or C) want to be a studio musician. Otherwise, reading FROM music is not usually called for - that is, 90% of all the music you think is awesome is done by musicians who aren't reading FROM music. More on this next time.
Play all notes no faster than you can play correctly. Practice makes permanent, so don't practice mistakes. Don't be impatient.