K', at this stage, being on your feet and working all day, I would consider some aches and discomfort normal. 3 weeks from surgery and 7 days from catheter removal is really early in the process. Your abdomen now has a small void where your prostate was, this means other organs have moved in to fill the space. Your bladder has been stitched up 7 ways to forever, amazing how many incisions and stitches they make to tie things back together to have a working urinary system afterwards. All of this requires weeks and months of healing to completely heal itself. I understand having to get back to your practice and all, but it's gonna be a strain on you until you recover a little more. Be very careful with weight limits and straining for a couple more weeks. I would use caution in lifting and pulling, tugging things ( teeth? LOL) for at least another 2 weeks, and use the donut pillow as needed. Nothing wrong with using it and being comfortable. The first week or so back to work will result in your dragging yourself home each night, worn out and hurting some, but each day will be less. If the penis tip pain continues, I'd say consult the doc, or if it were me, I'd probably put some neosporin on the head, just in case , and see if that relieves any.
Active exercise, increasing in duration and intensity after RP is recommended for quicker healing. Right now, the most you need to be doing is walking, I think. Gym and such comes maybe a month from now. Walking is good for you, speeds healing and recovery. I personally would walk as much as possible, and increase it as you build up. There's not much harm can come from walking now, and will be very beneficial to getting your stamina back. Also, increase the amount of water you drink, as you need to be hydrated well to heal quicker. So, if it were me, I'd walk as much as possible, breaking it up into 2 or 3 times a day, as your schedule allows. Good luck and keep us updated as to your progress on your journey. Oh, welcome to the other side, by the way. (almost missed that)..