Frequent urination and prostate cancer

I am a 30 year old male who exercises and eats right. I have been experiencing frequent urination along with a dull pain in my scrotal and pelvic area. I had blood work and urinalysis done that came back showing everything looks normal. There is a history of prostate cancer in my family. Is it possible for an underlying problem to still be there even though the test results came back negative and how is this possible? Also is it possible for testicular cancer to cause frequent urination? I also was diagnosed with mild scoliosis in high school. Is it possible that the curvature of the spine could be influencing my surrrounding organs (ex. the spine pressing against organs)therefore causing these problems. I also have an ultrasound scheduled for three weeks away on my scrotal and pelvic area because this is the earliest available appointment. Is this too long to wait and can the situation get worse in this timeframe.