I don't look German at all and have been living in berlin for 10 years. Never had this feeling.
...that being said, I'm Spanish and am sure that a guy from Pakistan will sadly get more looks, so YMMV.
And as for the city, came on! Berlin is so much more than clubs and drugs.
Berlin has a vibrant tech culture with user groups, meetups, conferences and hack groups. Probably the biggest scene in Europe.
Berlin has a cultural offer second to no other in the world. If you really like a band and want to watch them live, just wait and they'll come over.
Whatever you enjoy, you can find it in Berlin. Period.
Reducing Berlin to just clubs and drugs is absolutely ridiculous.
Spain has obviously better weather, that's a thing I miss from Spain.
The salaries are better in Germany, and I would say the working conditions are also better.
That's of course all my anecdotal experience, so YMMV. All but the weather.
And the food I guess? :)
Barca = Premium Berlin
> don't look like German? -> you'll get stares -> you'll be second rate / tourist / something
That depends on the corner of Berlin though.
There are plenty of user groups, technical meetups, hackerspaces, makerspaces:
c-base, Chaos Computer Club, Linux User Groups, JavaScript/Python/Haskell/PHP/... User Groups, Free Software Foundation local group, Wikipedia/Wikimedia stuff, Makerspaces, ...
Every evening more than one to choose from.
At those place - essentially, at every slightly nerdy place - everybody will try their best to talk to English with you, or the meetup will have English language and presentations in the first place, anyway. And people from different corners of the world are seen there as enriching and interesting people to talk with.
Ymmv
don't speak German? -> you'll receive bad service almost everywhere -> you won't get in to a lot of good clubs etc.
don't look like German? -> you'll get stares -> you'll be second rate / tourist / something
like drugs? like to party from 01AM to the afternoon of the next day? -> you'll love it
like sightseeing / going to the "best" places? -> everything's spread around a pretty big area -> you'll take the train / taxi / bus pretty often
like pretty buildings? -> in general, Berlin is ugly and crude. Except for the rich people areas and some places in downtown.
Partying two days without sleeping in the same club with a wide variety of substances is normal. There are weird sex club party thingies. There are ug techno parties with all kinds of debauchery. There are parks with more drug dealers than other people. Definitely not conservative, but somewhat xenophobic.