Seeing a drop of urine on the private part after making istinjaa

Assalamualikum. I follows Shafii Madhhab, hope that your answer also will be in Shafii Madhhab.
sometime after I make istinja a very tiny drop is seen at the tip of penis, sometimes I feel that something is dripping but I cant see any drop but sometime I see a drop on penis which doesnot flow (because it is very tiny) and also I check my underwear but I cant get any bad smell what will I do, because of this I am afraid to urinate and I only urinate 3 times a day and I am afraid if I get any disease Please help me what will I do?