I don't think you should try and clip them yourself. You might want to call your Vet and ask if you can bring him in just to clip his nails for you. In SD our Vets office had a walk in side they only did nail clips and shots and you didn't need to call for appointments.
Now that we are here in NC, I have no idea what we are going to do because I don't know any of the Vets out here. But I'm working on that, for now we are using Aunt Brenda's Vet when needed.
I would call and see, because two weeks is a long time, and if his nails are anything like Princess's he's going to need them clipped. Her's grow super fast.