@mauricepower
Got to remember you have a foreign device in our body. Yes over time the body will encapsulate the device and it usually results in less feeling of device and pain, etc.

However when placed below skin (mine is under chest muscle) movement of your muscles from your arm and chest can cause some irritation to the area around your device.

What I did when I first got mine was to remember when I felt pressure, irritation, etc. and what I was doing at that time and refrain from doing that.

I do water aerobics 5 days a week and we use our arms in all types of movements. I refrain from any exacerbate movements of my left arm that cause irritation or pain in the area of my device. I just do something else. I have found I know what is irritating the device or wires and don't even have to think anymore but remember to alter the movement.

I also found that sleeping on my left side put a lot of pressure in the area. I use a pillow to raise my upper body when sleep on my left side. I also use a pillow under each arm regardless of which side to prevent downward pressure onto chest.