Is this feeling normal?

I think it sounds like you are on the right track. This also happens to me. It usually means I want/need a session. I have two different types of horny now. Traditional where I like my penis stimulated and Aneros horny, where I want to ride my helix syn.

Absolutely fine, and actually congrats. You'll come to find the feeling can become very orgasmic and that you may start having frequent orgasm during sessions there. You're on the right path.

About six weeks ago I started noticing a new feeling in my prostate that has not happened previously... It's a combination of a mild ache, irritation and p-wave.

Congratulations, you are now the very conscious owner of an 'awakened' prostate. The "...mild ache,..." is your prostate telling you it is in want of attention just like the heart aches for the attention of a lover. The "...irritation..." is your prostate expressing its desire to be played with. The "...p-wave." is the bait to induce you to play.

This has increased my arousal to levels I have not seen in ten years and has actually improved my sessions. Could this be something related to rewiring or should I be concerned?

Absolutely it is related to your rewiring! This is all quite normal to the awakening process and you do not need to be concerned about it. As your practice proceeds these sensations will probably become less noticed as they become integrated into your normal daily life. I think it is important to acknowledge all these new sensations and welcome them into your life, this is your body expressing its amazing ability to supply you with enduring, rich pleasure as long as you are willing to eroticize these sensations as extensions of your innate sensuality. Good Vibes to You !