Side effects after saw palmetto.

Hi I took saw palmetto in 2016 April and beta sitosterol to block DHT and 5 alpha reductase coz I had hair losing problem , after one month I found I have erectile dysfunction problem , zero libido , I left the all this in June 2016 but after 2 yrs I have same problem still. I consulted with an urologist recent and I found my testosterone level is 3.38 ng/ml , I did also Scrotum , testis USG , it is found that my testis are smaller than normal and testicle also small in size , Dr gave me Tadfil 20 , but I didn't have erection problem , after this medicine my erection is ok , but I can't ejaculate sperm , and I can understand my testicles are small and penis too small since 2016 after having saw palmetto and beta sitosterol , What should I do ? Please help me .. Shall I counter this problem with Herbs ? Can i take Tribulus Terrestries after gym everyday ?