Hi and thanks for using the forum.
IF you are sexually active, then pregnancy is a possiblity. The only way to know for sure would be to take a test. You can take a test once you are due for your period (there are some tests that let you test up to 5 days before you are due for your period). IF your test is negative and your symptoms persist, you should see your doctor to find out what is going on. Other possiblities besides pregnancy include a thryoid issue or even a gastrointestinal issue. These can be looked into by your doctor. Good luck.
Bridget
You could be. I felt the same way before I found out. Except my nipples swole some. But you should take a pregnancy test just to make sure or go to your local health department and have one taken. Normally in the beginning of pregnancy a lot of women lose weight before they gain. It could be possible your further along that what you might expect. I was almost 8 wks before I found out I was pregnant