You will need to complete a self assessment tax form for the year and include your self employed profits and your employed earnings. That's the only way to tell if you are owed a tax refund.

You will need your basic Tax Return form, a self-employed page, and an employment page. If you haven't got all you need, phone the order line telephone number inside the front page.
Whether on not you are due a refund depends on your self-employed earnings. Emergency tax deducted should be approximately correct, and overpayment only arises if you have a backlog of unused tax allowances. It is also possible you are due extra tax on those earnings.
There is no way you will be considered for a refund until your Tax Return is sent back. Don't forget to tick the box claiming refund. If you don't, any money overpaid stays in your account towards any future liabilities.