Desire to control sounds is often what makes the disfluencies worse than they need to be. Ns and Ps are different from each other. With N, you need to make a sound on it and transition from the N to your vowel to whatever comes next. You can try making the N sound when you're alone by really looking at what happens when you make that sound. Say *Now*,*Never*, *Nobody*, *nasty* and feel how that N sound is created. Next time you're stuck on it, try to recreate that movement. P is different because it is a voiceless consonant. With P you need to get air out and just touch your lips. You can try the same exercise to get down the mechanics of the P sound. Try it with a range of words like *pear*, *polish*, *prance*, *ping* and really feel what's happening. Next time you feel stuck, try to emulate that movement. Just to note, in high stress/feared situations you probably wont be able to stop, think, and slowly work through the mechanics of each sound, but its good to practice when you get stuck in less feared situations to build a foundation.