Hi,I Am A 54 Yr Old Male,I Noticed Approximately 3

Hi,I am a 54 yr old male,I noticed approximately 3 yrs ago my stream was weaker, I have never had a prostate screen,and I believe I have had episodes of kidney stones in past,I hurt my knee approximately 3 weeks ago I started taking 1600mg of ibuprofen daily, this Tuesday at my work I did heavy physical activity then on Wednesday morning I used bathroom and urine made a double stream for a second then I went and sat down and felt a sensation like my total inside urethra was torn or scratched(the feeling lasted only 30 seconds) then I went to work and approximately 8 hrs later used bathroom and passed 2 string like clots approximately 1/2 inch long,I have no symptoms other then my weaker stream,just wondering if it could ibuprofen along with heavy lifting, or could I have passed a small kidney stone,or could I have a enlarged prostate and where I have left it untreated it has caused bleed?