[ozone]

I've read an article that said,"Don't just learn scales, Learn from scales".
Try to understand the relationship between chords and scales. Once you've figured that out you'll never get lost again. Playing with other people is a very valuable exprience that can't be substitued. Although learning theory is not the end all be all, you'll never regret having learned it.
Oh by the way don't be too hard on yourself, playing Santana tunes is not an easy task.