Please do not do this at this stage of the game. No 14 week old puppy needs leash pops with a choke chain. I would go with a martingale, which is nylon and will keep the dog from slipping a flat collar.Honestly she is acting like that due to excitement...
There are a few things that you could do to help.
1: Speed up the pace and get her more focused on moving forward with you instead of trying to move forward more... aka speed walk.
2: Get her calm and submissive before walking her, before putting the leash on her and even before leaving the house.
3: Collars. You have a few good options at 14 weeks and I would say go with either a standard collar high on the neck. You could also go with a choke chain for corrections. Make sure you keep the lead short and correct by a short snap of the wrist upwards and then relax after 1-2 seconds. Lighten the corrections the more the dog begins to comply. As stated treats can help with heeling and paying attention to you but even at 14 weeks the primary goal is to just get the dog to properly walk as if he/she is in a pack with you. From 14 weeks ~26 weeks is the terrible 2's of a puppies life and they will fight you more for control and dominance during this point in time.
A fourteen week old puppy does not need speedwalks to exercise them. In fact, slow down and smell the flowers with your pup. Let him check out everything in a nice easy laid back manner.
If he starts pulling, plant your feet and simply do not allow yourself to be pulled. When he slackens the leash start going again.
Perfect heel position, and all that, there is plenty of time for that down the line. Right now he is a puppy, a baby puppy, everything he is learning, house training - including what not to chew on, is enough for serious training.
Take him to puppy classes, use lots of treats and praise. Doing this right, you should never require a correction collar down the line.