I would have apprenticed time of birth to make the Vedic chart, without which it is not possible to interpret the Vedic way. However I see that your your date of birth is 16 July and you are Cancer born Girl, while the boy is 3rd Sept which is Virgo. This is what is called a 3-11 relationship. It is a relationship of gains and can be long lasting. There would be lot of attraction and attachment. But Moon native and Mercury Natives are always having strong different views. Both can never think alike and because of which they will indeed have difficulties in their relationship at times.
Regarding your other question, as per your horoscope you will have minimum 2 children. Chances of a Girl and a boy are strong.