Hi and Welcome to the forum!
First off I want to reassure you that what you describe is normal puppy behavior. I remember when we first brought Chessie home she would startle at anything new at first. As she gained confidence and secruity she got better.
It is also not unusual for a pup to piddle when someone reaches out to them. When I meet a new dog that is shy I usually crouch down, put my hand down at my side (with a yummy treat if possible), I don't look directly at the pup and I let the pup come to me!
We have a ton of kids in our neighborhood and of course they all wanted to meet the new puppy. I would sit them all down in a circle with some treats. My rule was ONE at a time they could call the pup to them, have her sit or down and pet her while giving her treat. This was a win win... they got to enjoy the pup and she was well socialized with kids... and I had 8 to 9 private trainers helping me! One thing I insisted was that the pup never be grabbed or forced... she had to want to go to them. It didn't take long before she figured out they had food. Perhaps you could modify this idea to work in the office.
Our Chessie didn't like my husband much at first either... then he started doing the AM feeding. It didn't take long before he was her new best friend LOL.
You might have noticed a theme... most Cockers are very food motivated.
Use that to your advantage. You can use his kibble for training if your worried about overfeeding. Enjoy that puppy... this time goes so fast!