Take 50€ and put it somewhere safe, your suitcase, your travel documents, wherever. This way you'll have it just in case.
If you visit the massive outdoor club Rio, also go next door to the 'Green Pardon' which is much cheaper, and has about 5 bars and three separate dance floors - all outside. Party till the sun rises!
German beer is all organic so you cant get hang overs - I dare you to test it! ;D FYI - make sure you have cash ahead of time because they don't take plastic and there isn't an ATM in sight!