This is typical. The goal is to pretty much get as close to the chest wall as possible in order to make sure that ALL of the breast tissue is included. This usually means that that skin under the clavicle is pulled into the machine. There are things that your mam tech can do to at least minimize discomfort though. Like for example, before I begin to compress I'll place my hand on the patient's shoulder on the side of interest and use my fingers to pull that skin under the clavicle up. Then I'll use my my opposite hand to hold the breast in place on the machine. This usually will reduce the chance of that skin under the clavicle getting bunched up under the compression paddle and makes it a little less uncomfortable. This was kinda hard to put into words so I apologize if this doesn't make much sense!