When working on oneself, one will have a better chance of feeling where the bottom of the follicle is, ASSUMING one is entering at the correct angle in the first place. The problem is, entering at the correct angle is difficult for a newbie working backwards or at a side angle.
If you need to, ask your mom to let you practice some insertions on a few leg hairs. Once you get to doing this right in the ideal conditions, you can go back and work on yourself and appreciate better what a good insertion is, and get down to working on proper placement inside the follicle for best treatment results.
Should you choose to ignore that advice, just set the galvanic at what ever treatment setting, and set the timing to 60 seconds or more, and do the two handed technique, where after inserting on the follicle, you hold onto the hair with one hand and keep the probe/needle in place with the other, and wait for the hair to fall out in your grasp. Take note of the time it took. If that is acceptable, reset the setting to that time. If you think that is too long to wait, retry this with a higher setting, while leaving the timing at 60 seconds, and take note again of when the time it takes to get release.
When you find an intensity and timing recipe that like, make note of it, and change the settings to reflect that, and go forward.
As for the pitting question, it happens because of many factors. Some, but not all are, improper insertions, too much treatment energy, cutting and slashing of the skin due to improper insertion or misapplied treatment energy.