If you earned 5k PROFITS and 10k this year , then you need to first calculate your 2013 tax liability (so tax on 5k). Ros should do this for you. By the end of October this year you'd need to pay this and also preliminary tax which is either 100% of last year's tax, or 90% of this year's. 100% of last year's is less in this case.
If 5k and 10k are your gross income then you'd need to deduct expenses (if any) to arrive at the profit figures. You'd need to be careful here and get advice on what exactly you can or can't deduct.
Edit: Whoops, just realised you only registered this year. You could then file a form 12 this year, and wouldnt need to file a form 11 until next year (and also pay preliminary tax next year too). Or, you could ring revenue and ask to change your registration to last year and file form 11 now. I actually had to do this and they were fine with it.