How high is the arrow? about an eigth? If the underside of the nock point is 1/2" high of square, then your arrow is probably about 3/16" which is a fine place to be, but it's also possible it's still too low. With NPs I always like to start generously high. I just eyeball the arrow square on the string, put one thumbnail bellow the nock, then just shift it with my other hand so it's like 3/8" high. This will create a very high NP. you can do whatever you think is the right thing in your arrow's case, but as you know a half inch high NP is like trying to peg it dead to rights on the first go. I prefer to start high, then there is only one direction to move it, and you won't experience masking symptoms like rest bounce that make it difficult to tell which way to move the nock.