Adoption after bio child

Hi everyone, I'm 45, single, have a 10 mth old son via IVF and donor sperm. I'm contemplating a second child but through adoption because of my age. I was hoping for frosties but that never happened and its too late to try again at 45. I was extremely lucky IVF worked the first time and I had very healthy eggs. But I don't have time to waste so when I was thinking about IVF, I also looked into foster/adopt. I decided that would be too hard, put it on hold, had my son, and now am considering straight adoption. I met with a adoption worker at a local social service agency already and have a packet to complete. It sat on my desk for about a week before I looked it over. I felt too overwhelmed and sometimes still do, wondering if I have the stamina to pursue it, and more importantly to handle 2 children. I don't have a lot of support, family lives 1.5 hrs away and I see them about once every other month. I'm trying to find daycare right now for my son and haven't had much luck trying to find babysitters. I moved to a large city 3 yrs ago for work and have a small group of friends. I just joined a mom/baby group to meet other moms and am hoping to make some lasting friendships. I'm on mat leave and return to work in a couple of months. I have a good job/career and do ok on my single salary, but don't own my own home, which I would like. I would also like to ultimately leave the big city to live in the country. I know that might be put on hold if I were to try to adopt because of expenses and also logistically. Lacking support and energy are the biggest deterrents for me. My parents are both deceased. I want my son to have a sibling and I always thought I would adopt. I keep thinking of long term. I know it'll be very hard when they are young, but I want them to having each other as they grow up and then when I'm gone. I can't predict how life will unfold, you never know how things are going to go, but I hope they end up close and have each other through their whole lives. I was an only child to my father and am the youngest of a big family of siblings from my mom. I had both worlds. I hated being my fathers only child and I loved my big family and have been around kids my whole life. Sorry for this loooong intro. I don't have specific questions, but just wanted to introduce myself and see if anyone has anything to advise me on re: adoption after having a bio child. Thanks!