I know , it's kind of DBA questions and they are excepting the Developer to answer it and I am a Newbie to SQL server ,and never faced such situations in realtime enviornment.
Yes these are real life scenarios that a DBA faces and the questions asked to you sound more like a discussion rather than questions.
They were probably trying to figure out what all you can think in a specific scenario. No answer is totally correct or totally wrong but they usually see how you think and whether you jump on conclusions straightaway.
If you are interested in an admin position and were not happy with the outcome of the interview, don't feel bad. Learn some SQL first. Be in position to understand simple procedures, functions etc. Read a lot to learn about scenarios. Then side by side, learn about admin stuff like taking backups, keeping log files intact on DEV server. This will make you ready for a junior DBA position. Discuss with the DBA about the things that you learn recently.
When you slowly are in touch with some DBAs, you might well be inducted into their groups to recieve some alerts. Try to find common patterns, send your understandings to the DBA.
At some point of time in your career, someone will definitely pick your enthusiasm and that will be your first breakthrough.
Don't give up and the best thing is to read and collect a lot of information.
All the best!