I bawled in terror for about 10 minutes straight after peeing on the stick, and seeing the little "plus" sign. All the while, my husband of 8 years was grinning and hooting and dancing around with joy.
I was 32, a career professional, and scared outta my wits. Then I took a deep breath, and did everything as "right" as I possibly could, thereafter. As the birth approached I was still worried that I wouldn't like or love or bond with the baby -- but that wasn't the case at all (luckily). When he came out, it was the only time I've ever experienced love at first sight.
17 years later, hubbie is long gone (his joy of fatherhood and husbandhood passed 3 years after son was born), and my son and I are still going strong. We're a great team. I still have to take a deep breath, and try to do everything "right", but I don't have that 10 minutes of sobbing terror much anymore.
I have a great boyfriend that my son calls "Dad", and he helps a lot too.
You'll be fine. There's never a perfect time to have a baby, but you'll be strong enough to nut up, and handle it. Try to have the discussion with your partner about being good parents, even if you do not stay together. Not that I'm denigrating your relationship, but shit happens, sometimes.
Good luck!