Good luck man! If I hear your Dad cheering you on in English I'll stop over and say hello.
There's a seemingly nice amount of us ex-pats here in Berlin, but not enough of them are trying out BJJ. Personally, because I felt this way too, I think it is a fear of language being a barrier, but I have learned more German from BJJ than just about any other place. Plus, lots of people speak English in Berlin...so I find it pretty cool that you train here in Germany.
Not sure how long you are staying here in Berlin, but if you guys want some places to go eat I'll send some your way. There is a GREAT burger and steak joint near where the tourney is that is owned by Americans and might take some homesickness away, but you'll need a reservation. Totally worth it for the hot wings (IMO).