Excited but...

My husband and I have been together for 7 years. This November we decided we were going to start a family. It took 1 month. We were shocked. My husband owns his own business and works long hours... he wasn't officially ready to bite the bullet but knew it was time. I'm 12 weeks and 5'0 so I've already started showing to those who know the news. I get asked ALOT "aren't you excited?!" Of course I reply "Yeah"... but I'm wondering if there is something wrong?.. we heard the heartbeat at 9 weeks and I assumed I would cry but I didn't. I heard the heart beat again at 11 and same thing. It was cool but not just overly excited or happy or anxious..? I actually feel bad when people ask if I'm excited because I am but not near as excited as they are. Is this normal?? I told my husband and I said I think it's because I don't know what we are having, I can't feel it, and it's just doesn't seem real? OoO I haven't had ANY symptoms of being pregnant except for a little night being quizy... I'm just worried I'm not as excited as I should be and something is wrong with me??