Should I be concerned if my tax return status is still in the accepted stage after three days?

[DoninGA]

Nothing to be concerned about, that is not unusual.

After the tax return has been Accepted by the IRS (meaning only that they received the return) it will be in the Processing mode until the tax refund has been Approved and then an Issue Date will be available on the IRS website.
See this IRS website for federal tax refund FAQ's - https://www.irs.gov/refunds/tax-season-refund-frequently-asked-questions

[Cynthiad66]

No you should not be concerned.  There could be several reasons why your return is pending.  See this link for more details.  What Does Pending Mean