No, filing as Single with two dependents probably won't be rejected, although you can hope it gets rejected for another reason.
As you probably know, if your return is rejected, then you can re-enter the return, make changes, and e-file it as if for the first time.
But if the return is accepted, then you will have to amend your return either in a few weeks or when you receive your refund.
To learn more information on how to amend your return, please see this TurboTax FAQ: https://ttlc.intuit.com/replies/3288565
So by ammending my return, I can possibly get more money in my refund just because I'll change my filing status to Head of Household?
In terms of changing status from Single to HOH, your tax bill will probably be reduced (HOH qualifies for lower tax rates and a larger Standard Deduction).
I claimed single with one dependent, will this cause the irs to hold my refund?
Filing single with one dependent may delay your refund if you are receiving the Earned Income Tax Credit or Advanced Child Tax Credit @rcast08.
By law the IRS started processing those returns later than some other types of returns to allow additional time to help the IRS stop fraudulent refunds from being issued.
Check Where’s My Refund? for the status of your refund. The site is updated every day.
I filed 2/2 turbo tax didn't tell me anything about filing single with a dependent - this is my first child. I am on hold since forever- do I need to make an amend change or will they still process it. No letters from the irs but no income either
@rcast08 Do not try to change anything on your return until it has been fully processed. AFTER it has been processed if you need to amend to change your filing status to Head of Household you can do that by using a special form---Form 1040X. Sit tight and wait for the IRS to finish processing your return.
Meanwhile...
Am I Head of Household?
https://ttlc.intuit.com/questions/1894553-do-i-qualify-for-head-of-household
https://ttlc.intuit.com/questions/2900097-what-is-a-qualifying-person-for-head-of-household
If you qualify as Head of Household, when you enter your marital status (single or married filing separately) into MyInfo, and then enter your qualifying dependent, TurboTax will offer HOH as your filing status.