Hi Taliska
Where are you grooming your pup? It's usually to groom them off the floor - a table is good, but be careful as they can sometimes be a bit kamikazee the first few times !
As for the trimming the feet - never trim between the pads - you should be trimming "across" them, so the fur should kinda be level with the pads. Also never trim between the toes or your pup will end up with feet that look like a poodles! the aim for the feet is to look like cats paws.
The wriggling etc should stop as your pup gets older, but at the moment he justs wants to play wth everything. Firmness and perserverance is the key - if your pup is biting you use your NO word to convince him to stop. When the pup is standing quietly plenty of gentle praise, and perhaps a tasty treat
Remember to never end on a bad note when grooming, especially if the pup is wriggling or he will start to learn that by wriggling lots, you stop brushing
Millie can be a fidget when being groomed, a firm "stand and stay" usually works for me, then after a few minutes of gentle praise and patient standing I give her a milky bone and then continue grooming.
HTH
Kelly
edited to add - perhaps it might be a good idea to groom him after he has had some play time, and is a little less excitable - obviously don't interfere with his sleeping though