I think you should stop thinking about it. Yes, easier said than done but let go of it for now. You have tons of time (biologically and in all other ways). When I was young, I steadfastly didn't want kids and I figured someday I'd have a long-term, live together relationship but not marriage, not for me. Well I ended up getting married at 26 to the best person I could hope to meet. And at 38, seemingly out of nowhere, I've done a 180 on kids and I'm trying to conceive. I'm sharing my history to illustrate a point. You'll never be able to predict the future. Not just what will happen but how you'll feel about it. So try to take a deep breath and cut yourself some slack. You can't decide it all today. I don't mean that you shouldn't, you actually can't. Let each small choice inform your next choice and so on. Give yourself a chance to actually build a life, not build a mold for the life you think you may want. Please don't be so hard on yourself and allow for happiness to find you in ways you don't even expect.