Yep, feet can be tricky on lots of dogs. Something I evaluate on temperament testing. When I worked for a vet I lost count of how many dogs were terrific for shots, ear exams and then went ballistic when the owner casually asked for a toe nail trim. I have seen dogs scream and bite and fight and express their anal glands during a toe nail trim. I disagree with fighting and "getting the job done" and muzzling the dog for toe nail trims. This just reinforces the dogs belief that nail trims are "bad". I do extensive training on feet. If the dog is ticklish you can hold the leg and support the foot rather than grab the foot.
I do an exercise I call "touch the feet"... I touch and food reward, tickle and food reward...eventually work up to hold and put slight pressure, and giving food reward. You want the dog excited and happy when you grab a foot. That is what you work toward. Old dogs can benefit from these foot exercises. They actually learn to enjoy the game. Go slow and back up and start from the beginning if you get stress or resistance. I use the dremmel rather than nippers because most of my dogs prefer it. It does provide a issue with coated breeds for obvious reasons.
I trim the hair on the bottoms of my dogs feet too. Eliminate "slipper feet"... that takes time and training too. Always find a "tummy rub" person and do not let the tummy person get their face near the dogs face. Often you think you are doing great and the dog will take a swipe at the holder. Prevent the bite and use caution during nail trims.
On the muzzle comment I just made... I always teach my dogs to wear a muzzle on command. I slip on a muzzle or tie the mouth closed.. then I take it off with a "good" comment and give a treat right away. You can work up to your dog getting happy and excited when you get out the muzzle and a dog grinning at you with the muzzle on because the treat is coming and they know it. Teaching a dog to accept restraint and love to be held for vet exams will make your pup your vets favorite client. Folks train horses to stand for the vet and farrier but don't think about training their pups and dogs to stand quiet for exams. If your dog is ever hurt badly you might need a muzzle in an emergency. The time to introduce the muzzle is not when your dog is already stressed out or hurt. I have one dog that I know will bite at the vet when stressed. I bring his "own" muzzle, put it on myself, the vet does the shot or exam and when finished I remove the muzzle myself and give a treat. No stress. It really works. My dogs love going to the vets office because they are prepared and trained for it.
Think of all the things your vet does and do it at home and with treats. Lift the tail and look at the butt. Haha. That one will make your dog say "what the?" .... give a treat right away and praise. I could go on and on of all the interesting things you can do to train your puppy to enjoy handling. Now is the time.
ps, love the name, my daughters nick name is Lu Lu