Hello, I just noticed I incorrectly filed single instead of head of household do I need to amend my return, if not will this delay my refund?

If you have already submitted your return to the Irs and it was accepted, you will need to wait until you receive your refund in order to Amend or Correct the return. These forms have to be mailed in directly to the Irs.

https://ttlc.intuit.com/replies/5785990