Not bonding with baby bump?

Nicole
Hi,
I'm 14 weeks pregnant with our rainbow baby (had 2 miscarriages last year) and I just don't feel like I'm bonding or it's sunk in yet. 
I love looking at the scan pictures and buying things etc but I just don't believe that I'll actually end up with a baby. I've had such a bad time in the past I can't stop thinking it won't happen so I don't want to get attached as I'll be heartbroken again. I worry before every scan that there won't be a heartbeat or I'll have reduced movements and something will go wrong.
On the other hand I don't want to spend the whole time being guarded as I don't want to ruin the pregnancy. 
Has anyone else had this experience? Thanks x