I'm only about 4 weeks pregnant. Can stress affect my baby?

I'm a college student that just found out I'm pregnant. I have midterms, important speeches, research papers due, etc. Also, and whats stressing me out the most is that my future husband has gone away to visit his family, and he'll be gone for about 3 months. I really miss him and I've been crying non-stop, I can't eat and I only get a few hours of sleep. So, my question is: Will all this stress affect my baby even though its very early in the pregnancy?