Hi there, try not to be too hard on yourself. Pregnancy is hard, physically and emotionally, at the best of times let alone when you are so young. I would strongly suggest that you confide in your midwife and/or GP because you need to find some strong support for you, perhaps a bumps and baby group?
I was a Mum for the first time at 19 with my family over a 100 miles away and I found it incredibly hard. My ex husband (the dad) was not particularly helpful and after I had my son trying to cope made me postnatally depressed which was recognized but not treated properly for two years.
What I would suggest to you is that you try to reflect on the root of your fears and anxiety that relate to your age, relationships, money, hopes for the future - whatever is the most important thing to you, and be honest with yourself. At 17 you're having to come to terms with motherhood at the same time you're becoming an adult (legally) . Your relationship with your boyfriend will come under strain too because pregnancy for men is scary and for young men more so, quite simply men don't really understand much of what is happening within our bodies as the baby grows. Try not to take your stress out on him, because all that will happen is a cycle of arguments and you feeling worse. It's sometimes easier to be awful to the people we love because it feels better (at the time) than allowing ourselves to be vulnerable, but it just pushes our loved ones further away.
With regard to your family, are you able to reach out and build stronger relationships? I would suggest you try, if you can. When I had my son, it brought up all sorts of feelings about my own childhood (which was dysfunctional due to divorce and other difficulties) and about what I perceived to be the failings of my own parents. One of the toughest things I have had to come to terms with is as a parent you can only do your best and only now as a parent and after the loss of my Dad last year, do I truly accept that my parents did their best for me, in the circumstances, at the time.
I really feel for you, because you've got so many things to think about.
Please be kind to yourself, stop trying to do too much, and keep talking rather than bottling it up. You and your boyfriend have so much to look forward to together. being a young parent is hard but so rewarding, I truly wish you all well, hugs x