I'm having this problem with losing some of my product before injecting. When I swap out the needle tips after drawing the product out and putting a new needle on for injection, I think the old tip keeps some fluid with it because after I push any existing air out with the new tip, I lose about one line's worth of product before I inject. Do you guys always put one line above to acquire for this loss or am I doing something wrong? I dont want to keep filling it one line above then get to the last shot and only have half of a shot's worth, or do the vials come slightly overfilled for the issue? Thanks