Adgal has it right!! If I were you I would go buy a HPT. Definately track your ovulation if you dont think you are. (its HALF the battle) Then your dr can do some blood work/exam to determine what ovulation meds to put you on. They affect each woman different my cousin has twins using ovulation meds as she started ovulating multiple eggs from each ovary. Good luck to you and have fun!!
Just one of the women who swears by preseed, I think I sorta got it started here, I got pregnant my first time using it, it made me a believer.......
Not everyone gets that discharge. I do from time to time, but not always. All that mucus does is help create a more fertile enviroment for the sperm, which increases your chances. Kind of like a natural lube your body produces. Dont use a normal lubricant, because even if they don't say they contain spermicide, they can still interfer. Someone on this site told me about a product called preseed, which mimics the natural stuff your body produces. I ordered it (it was about $20.00), and there are women that swear by it. The website is www.preseed.com. I also use an ovulation kit (buy a decent one, I use the clearblue easy digital), which will tell you you are about to ovulate (12-48 hours ahead of time). It works great, I have gotten pregnant twice using it, and am waiting now to find out if I am pregnant again.
If your cycles are normally 28 days, it sounds like you could probably take an HPT now to find out if you are or not. You could be having pre period symptoms, or it could be early pregnancy symptoms. If you aren't, and you really think you aren't ovulating, I would try to get in to see a fertility specialist.
Sorry such a lengthy answer, but I wish you luck!!