Unanswered questions from medical doctors

[tiger1234]

Hi, I am 19 years old and about 8 months ago I noticed what appeared to be the symptoms of UTI (burning urination, frequent urges to go, light bleeding when urinating), so I went to the gynocologist. I was considered it could be an STD, but she checked me out and said it is not an STD and gave me an antibiotic for UTI. As soon as I took the antibiotic the symptoms went away but a couple of days later the test results came back explaining that it was not a UTI. Within that week I came down with "flu-like" systems that lasted about three days. After this I was fine and never experienced any burning urination of sickness. This left me puzzled though because I wondered what it could be. I went to two different doctors, one of them labeled it as a virus that had been going around and the other sent me to get a sonogram of my kidneys. Everything came back fine.  I had explained to the doctor that I was on and off Zoloft during this period but he said that shouldn't have had the affects I was experiencing. He never mentioned that It could be an STD or anything like that either. Could three doctors fail to notice? And also during this time period I had not received a period for about 6 months. I have felt fine since, aside from the missing period...and have also visited the gyno last month for my annual check up and she said it's normal for some girls to be irregular. Any advice? or should I be worried?