Unless you've had two DXA's at the same place, and can measure any difference in the results, you won't know if you have bone loss.
For people whose first DXA results in a low score, it's a toss up as to whether your bone density has always been low as a result of not building up your maximum bone mass during your bone forming years or whether there's something else going on that would cause your bone density to be low.
If your blood tests are normal and you've had hormone tests that are normal, other reasons it could be low at your age would be a chronic medical problem you've had, such as an illness that necessitated your use of steroids or anti-seizure meds, anorexia or bulimia or another condition that impeded calcium absorption, low Vit D levels, your genetic makeup (look at your parents/grandparents) amenorrhea, heavy alcohol consumption, the use of depo provera birth control shots. Any number of reasons your score could be low. It could even be that you're going through an early menopause.
What we see now are young women with low bone density because of environmental changes in our culture. They are smoking, reducing their milk intake by replacing it with soda, not going outside for recreation, thereby reducing their exposure to the sun (use of sunscreens too) and exercise. More kids are indoors on computers, video games, etc and aren't getting adequate PE in school anymore. We're seeing the results of these lifestyles show up in our osteoporosis center with stress fractures. Girls especially are prone to this as they are concerned about their weight and forego a healthy diet with exercise.
At 35, you've already reached the maximum bone density you'll have. What you need to focus on now is preserving that, and if your doctor has ruled out any medical reason for this, not losing any more bone mass.
Look at the NOF website for information on this.
www.nof.org There's a really good FAQ section that has a lot of good advice and information for you.