If you've TURNED OVER 6K, don't bother with an accountant; just sit down and do your tax return; it's simple if your turnover is less than 15K, since you just do the 'short one'.
I think you only have to fill in a couple of boxes, leaving blank the ones that don't apply; but it'll only be putting down your turnover, your expenses and your profit (the difference between the two).
You'll be taxed on your profit, after your personal allowance has been deducted; so your tax bill will be very low, almost nothing; if any at all.
Still, £500 per month sounds really low to me.