Your employer must be good then. Lots of companies don't hire and fire sick employees. Actually it's generally advised not to share one's medeical information at workplace.
I even read recently about the case of a worker who wasn't promoted despite everyone else expected him to be promoted. His sin ? He told briefly one of his colleagues that his car got stuck and he was tired of fixing it every now and then.
The promotion involves commuting for a certain distance. His manager told him he would have promoted him but he heard his car was not fit.
In Germany, depending on the type and seriousness of your diabetes, you can get officially recognized as handicapped, and companies above a certain size (20 employees) are obligated to have a certain number of handicapped employees - so an employee who is handicapped, but can work (more or less) the same as a normal employee is actually a win-win situation.
Actually, the sensor is super easy to hide (especially with long sleeves) and injecting is also quite discreet these days. I've seen injectors that are about the size of a marker or a wireless earbuds case. It's easy enough to go to the bathroom right before lunch or when you get an notification on your phone.
I'm not diabetic but I'm pretty sure what you describe would cause a lot of stress, especially if you don't want anybody in the office to find out... "hey you have a small bladder maybe?"
Stress has an impact on sugar levels, making it harder to regulate.
If you think knowing of the medical condition is bad for your career at your current employer, maybe it is better to switch employers.
I even read recently about the case of a worker who wasn't promoted despite everyone else expected him to be promoted. His sin ? He told briefly one of his colleagues that his car got stuck and he was tired of fixing it every now and then.
The promotion involves commuting for a certain distance. His manager told him he would have promoted him but he heard his car was not fit.