If you're originally from Germany, you will be forced to leave the UK anyway. In a sense, getting people like you out of the country was a big part of the whole Brexit proposition...
There is no need for sarcasm. Of course nobody knows the terms already, but I'm talking about the rhetoric that was used to promote the Brexit. And "getting the foreigners out of the country" was a big one. All signs point to this becoming true, because these are the same people who will be spearheading the negotiations.
This isn't necessarily the case. Many EU migrants will be able to claim residency in the UK if they meet certain criteria.
In all likelihood the UK will join the EEA and retain free movement, but even if not, economic migration will still be encouraged and a visa system will be in place, just as the country has for the rest of the world.