Get used to seeing some changes in urine flow when doing hard PE. Almost any rigorous routine causes edema. When the swelling is sufficient to the meatus it can cause your urine stream to come out in split streams or crooked streams making a mess on the floor. After an intense session I have to actually sit to urinate. You may be overdoing the newbie routine, could have bruised the urethra, but the slow stream is probably just caused be the lymphatic swelling that goes along with this obsession we call PE. Slow and steady wins the race.
I once pissed on a guy’s shoe standing next to me at a urinal. It was not a pretty scene.