Just from the small bit you have said, I would say excess testosterone, although at one time, I had excess testosterone AND excess estrogen. Excess estrogen causes heavy, frequent periods at some point, and although spotting between periods is part of it, missed periods are rare. Also excess estrogen causes easy weight gain, while testosterone helps prevent that.

Don't know how old you are, but hormone testing in late teens, early twenties, some excess of hormones is normal. If you are over 30, search perimenopause on the women's forum.

IMHO, the main cause of hormonal imbalance is an excess of fried foods/bad fats/snacks and the lack of very good fats.

Also sounds like you may be a little anemic. If you don't want to pay for tests, go give blood and they will tell you if your hemoglobin is low as they will test it before you can give. Or you can eat a lot of dark greens and red meat for about three weeks and see if you have a change in symptoms.

Scars that never heal makes me think of diabetes. Is it possible in your desire to gain weight you are getting high Sugar levels from the food you are eating?

Actually, sometimes tests are not necessary. Just eating very clean non processed food - ONLY - for a few months sometimes makes the changes our bodies need.