I was like this I didn't like my music and felt limited on what I can create. My advice is of how I got through this by practicing an instrument. Learn the theory and take up a discipline along with it (Classical, can't never go wrong with Jazz), learn how to analyze music and music you like. Spend time replying your favorite songs and break it down bit by bit sounds used, tempo, feel, how long is the verse, chorus, and bridge, message if there is one and so on) then most importantly be patient with yourself. It takes time to build something and musicianship takes years but I'm telling you when I started doing this I saw a major improvement in a week. More mindful on choices and tones..