Hallow Dear,
On this platform of HCM, I will try to be of use to you. Let us consider the issues one by one.
1. Virginity you are referring to is intact
Hymen. Hymen is a membrane present at the vaginal opening. In good old days, it used to get ruptured during the first intercourse. However, now due to changing life styles of girls, the situation has changed. The hymen can get ruptured even by sitting astride like riding bicycle, motorcycle, horse riding, climbing trees, athletics, etc. Should you be really bothered about your ruptured hymen? If at all so, then you can get it resutured surgically. However, I do not feel it is essential. Instead, both of you being loyal to each other after marriage is more important.
2. Your weight for your age and height is low indeed. It is governed by numerous factors; some of them are:
a. Less or low quality diet
b. Over exertion
c. Genetic or Familial deposition
d. Hyperthyroidism
e. Some debilitating diseases like tuberculosis
f. And many other causes
You have to first analyse the cause honestly with yourself. Get medically examined from a doctor to rule out pathological causes. If they are present, you may require some treatment. If your familial size is thin, you can hardly do anything. Improving diet, controlling overexertion is in your hands.
I hope you are satisfied now.