Your hormone level does suggest you are in menopause. Although the mean age of menopause in the United States is 51, and the range is from 45 to 55, there are about 1 - 2% of women who go into menopause before age 40. That is called premature menopause. Some women can go into menopause even in their 20s or teens. Since you were on the pill which makes FSH levels lower, you might have been in menopause for some time and just didn't know it. It does not mean you are "abnormal". It is just atypical or less common.
Since you are in premature menopause, talk to your doctor about whether or not you want to continue on estrogen. Get a bone density to know the baseline levels of your bones' thickness, and talk about a treatment plan.
Although some women do rarely restart their periods, it is very uncommon.
Machelle M. Seibel, MD