Hit a car and drove off (U.K)

So I know this probably isn't the place to put this but on Saturday morning i hit the back of someone car and in sheer panic drove off. I know how competely stupid I was and I felt guilty about it all weekend. I went to my car last night and found a note from the people who's car I hit and I messaged them explaining how awful I felt and how irresponsible I had been but in a sheer panic I drove off and gave them my insurance details.

They have messaged back and have been really amazing and understanding about it which is more than I deserve and they have contacted my insurance company, but now I'm petrified I'm going to get into so much trouble for driving off! I'm 6 months pregnant and the first thing that came to my head was to park and ring the hospital for advice, they told me to rest and monitor for the rest of the weekend, which is what I did but I'm just so panicked.