When you set the goal as "getting married and having kids" then you have a tendency to slip into the mindset of "the means justifies the end result".
What I mean by that is your goal should be finding the right man for you and see where it leads. Otherwise you become one of those typical women who want marriage/kids at all costs, and end up marrying the man they shouldnt have simply to fullfil their goal of marriage/kids.
Its a subtle distinction and initially you might say "duh, of course Im going to look for the right guy" but as time wears on and you start to confuse not being married with kids as some sort of personal failure and then you are willing to marry lesser men just because they are available.
Youre only 24 which is why i bring this up in the first place. If you are 34 and not married with kids hopefully you wont think "gosh Ive done all this work towards this goal and it hasnt happened yet, whats wrong with me". Sometimes it just doesnt happen and most certainly shouldnt be forced for the sake of the "goal". You more than likely will be a different person at 34.
Have you given any serious thought about what you would get out of marriage that you wouldnt already get without it? You say that you panick or get cold feet when things get serious, why is that?