"Stuck at the PXE boot screen" sounds like you end up in WinPE. If you are, simply reboot.
Before doing so, restart the Netboot_Server service on the PXE server / Site server to which the client connects for PXE. You loose NOTHING if you hard-reboot from a WinPE screen.
If you mean it's literally in the PXE boot menu (odd) that you get when bootinf from a NIC, just bounce it.