Scared to have a baby?

I am 25 yrs old, married for 2 yrs, have dated my husband before marriage for 5 yrs. My husband is 29 yrs old.There is no problem what-so-ever between us. But I am extremely scared to have a baby. Actually I don't want to wait very long to have a baby, as I am seeing couples around me facing problems conceiving, so I don't want to wait till my late twenties. I have calculated that if I start planning from now, I will have a baby by end of 26, and biologically it seems the perfect time. But mentally I am traumatised. When ever I think of getting pregnant it scares my wits off. I feel so scared , that there has been times when my husband is happily imagining that we will have a baby who should look just like me, just me the smaller size, and all such cute talks, and I cut him short, and shout at him saying, I don't want to have a baby. Such a fight happened yesterday, and though we have sorted it out, for my husband is a darling, I am feeling very guilty to hurt his feelings so much. My hubby gets so happy when we talk about babies. Last time when I missed my periods for a few days, he was jumping with joy, brought his ears near my tummy,knocked my tummy and said, "Snuggles are you in there?" Then again he imitated as if the baby is talking, and said,"yes daddy, I am here". But the bad thing about all this was, I was extremely tensed and did not enjoy even one bit. All I was thinking about was, what will happen if I really am pregnant and I was almost in tears. When I finally had my periods, I was so relieved. I am so particular about this thing that I did not have unsafe for all these years till last month, and if by chance we had done it, I would take emergency contraceptive pills. But this month we had unprotected , but he d outside every time so though there is little chance of being pregnant there still is chance. And I am freaked out. Though at that time it felt great, and I was determined, now I am very scared. Why am I feeling like this? Is this normal, for women of my age to experience? How do I start preparing myself to have a baby? Actually, every time I think of having a baby I think of the 9 months, and the birth process and the sleepless nights, and the responsibility. I am very worried thinking whether I will be able to handle all this pressure. I also have a career which I don't want to lose, though I am mentally prepared to give my career a break for a year after the baby comes, I will never be able to be a complete homemaker, for I love to go to work. i don't want to wait too long. How to I make myself love having a baby. Please post genuine answers, as I am really facing problems.