I had a HORRIBLE day (for trumpet playing) and it's my first one in a while. I've been practicing efficiently for 3 hours everyday this summer and things have been going really well. Today, I was doing some buzzing in The Buzzing Book by James Thompson for warm up and that went alright. However, when I went to play some flow studies on the horn, I couldn't even hit a G just above the staff (my highest note is usually C# or D). I moved on to a tonguing etude, and my chops didn't last half way. The only thing that hadn't changed was my ability to lip slur. I feel like all my hard work has gone to waste, because my playing today was SO BAD. Any advice?