I'm having trouble hitting shots when I don't do a full swing. I don't know what I'm doing wrong but I very often hit shots that go very low and off to the right at about 60 degrees! This is very embarrasing when I'm on a very public pitch and putt course where the fairways and holes are all close together.

I go to the local pitch and putt for practice with this and shoot higher scores than on the full courses lol.

Today at the range I tried hitting some 50 yards and in shots off the mat with my sandwedge and the first dozen I hit were near perfect and I was really happy. I wasn't even paying attention to the line of my feet it didn't seem to matter. Then I choked further down on the grip to hit it shorter (as I was hitting it 40-50 yards with just a hip-height shot) and up popped the problem of the ball flying off to the right. I put my hands back to the top of the grip and was still doing this shot and got really frustrated. I must have hit 10-15 balls on the trot that all did this before I hit my last 2 balls as full shots which were fine.