Just like those who going through this burning session during urinating, it's quite common. Since wife is a nurse and I used to work in the medical field, I'll share with you some of the knowledge in this arena. I'm going through it myself again as I'm resuming my enhancement to satisfy my woman.
When you start fresh or resuming after a long time, as DLD indicated, your urethra is experiencing compression after a wellness period. Compression due to the device(s) pressuring either at the end of your urethat (your penile tip) or the first 3 inches of your urethra's pathway where most of the nerves are at the highest in sensitivity. The compression will cause your urethra to require more force to push the fluid through, and of course, make a crap loads of messes as the stream splits into two or even three directions.
When that happens, allow the penis to relax in a warm compress and massage the 3-inch length from the penis tip in a rolling motion. Make sure to also drink less acidic fluid to prevent that burning session as well. I drink from green to oolong tea, and it helps quite a bit on intense
hanging, pumping,and stretching days.