People who have had similar experiences, advice please?

I got married to my husband when I was 25. At the time, we were not financially or mentally ready to have a child, so we decided to put that off for the time being. After 3 years of blissful marriage, I shockingly found that I was pregnant. We were devastated. Both my husband and I walked around for 3 miserable weeks trying to decide what to do, until I had a miscarriage. Though neither of us wanted to have the child, and were leaning toward getting an abortion, we were devastated again. So, we decided not to have children. However, 4 years ped and we started to think about children for the first time. We were financially secure, and ready. We decided to adopt a child, and then have a child. We found a 15-year-old boy who we instantly clicked with. We have filled out all the paper work, and are going to bring the child home soon. Just 3 months ago, we also discovered that we were pregnant. What will it be like, adopting a 15 year old? What about having children with a 16-year age difference? Will it be odd, that my husband and I are only 34 and 32, yet we have a 15 year old? Sorry for this being so long, but if you have had a similar experience to any part of what we are doing (children with large age gap, adopting a teenager, etc.), please tell me what it is like.