4w2d: A little scared and worried

I know I shouldn't be worrying.  The nurse and midwife who I spoke to on the phone both reassured me on 2 separate occasions that this is totally normal, but it is the most disconcerting thing on the planet to see when you're pregnant- brown spotting.  It isn't heavy, only at times accompanied by cramps, but yet, despite being told it's normal, I still worry that this baby is not going to be with us for long.  I cried for a bit this morning thinking that we could be losing our baby, and I'm praying so hard for the bean to stick, and I know that no matter what I do, it's all in God's hands now.  Please let this little one stick.  I didn't think I was attached yet, but I am, and I want this baby to stick so much.