no thrush or manifest yeast infections--could I still have candida?

Hello everyone! I've been concerned about a possible candida problem for some time now because of certain symptoms that I can't seem to link to anything else. These are primarily: fatigue, Sugar cravings, congestion, anxiety/OCD, no sex drive, and digestive problems (constipation, diarrhea, bloating, etc.). However, I don't have oral thrush or trouble with vaginal yeast. And I don't get fungal infections on my skin or nails (although I did as a child). I have also not taken any Antibiotics in years, unless oral contraceptives count as an antibiotic. I have taken birth control pills for 7 years. It seems that most people develop candida issues after courses of Antibiotics or corticosteroids. Actually, I did have to take Prednizone for about a week several years ago. But that was the only time. Generally, I try to eat healthfully and stay away from refined Sugar as best as I can. I also get plenty of exercise and drink lots of water, etc. Additionally, I have used various anti-fungals on and off for the past year and a half with no real results (Three Lac, grapefruit seed extract, capryllic acid, oregano oil, etc.). So I guess my question is: how likely is it that I'm dealing with a yeast overgrowth? Should I consider trying to get my hands on a prescription anti-fungal? I worry about this issue all the time, and I would really like to stop worrying so much, especially if it is unnessary anxiety. Is there an accurate method of checking for candida? I've had stool sample screening and various blood work done, but nothing abnormal was found. Of course, I'm sure they weren't checking specifically for yeast. But wouldn't a yeast overgrowth throw other things off, making it obvious that there was an imbalance of some sort in the body? Please give me your thoughts on this. How likely is it that my problems are related to yeast, and if they are, what is the best way for me to deal with it?