Watery discharge or fluid ?!

Im 18 weeks pregnant for now 1 week ive been noticing when i urinate behind that I leak. I dont soak my under wear or feel the leak its only when I put pressure to Pee I can see drops I had an appoiment with my ob he only did an US which shows my fluid was full but Im worryed when i go back it can be low because of a slow leak I did have a Subchorionic hematoma at 12 weeks just stopped bleeding 2 weeks ago