Chosen Solution

So my watch didn’t even fall down from 0,5m on the backside. My screen didnt broke at all, but I got a small crack on the other side, where the optical heart sensor is placed. My question is: Is there any possibility to change only the optical heart sensor with the glass ? Because I think since it broke, my battery goes empty much faster and it’s getting me in real trouble :/ it lasts now only about 6-8h. Thank you guys for the answers!

Apple is the best place to get your watch fixed Update (01/16/2019) As you can see its a bit of work to even get to the sensor unit Apple Watch Series 4 Teardown.