TDS for a payment to a professional

I have been taking the services of a professional for 5 months. We had agreed to a payment of Rs 10,000 per month. So, first 3 months I didn't deduct any TDS as the total amount paid was less than Rs 30,000 but from the 4th month onwards, I started paying Rs 9,000 only deducting 10% as TDS.

So in the 4th and 5th months, I deducted TDS. Is it the right thing I did?

Or should I have deducted tax for all the 5 months?