I try to practice every day of the work week, every morning before work. Weekends are pretty much a crap shoot, because we always have lots of stuff going on, but I never miss practices during the week. It seems that I'm often crunched for time and some days can only muster a 15-minute warm-up and a few exercises. I find I'm then rushed to get to work on time and so start the day (and sometimes the week) in a very poor frame of mind. Mondays seem to be the worst days, but they are by no means exclusive.
So the last two weeks I just skipped Monday. Didn't even try. I took my time with breakfast, got to work early, got my week kicked off in an orderly fashion, put in some extra time on the clock and got stuff done, then had Tues-Fri to practice leisurely for an hour or more each day.
I found I was more focused and had much better practices. I didn't feel rushed or stressed, and that made it easier to play correctly without too much pressure. I also found myself paying closer attention to the details, and avoiding mistakes.
More importantly, I find I'm enjoying the trumpet a lot more than I have in a while.