No, it's not absolutely necessary, you should be fine.
If you want a pre, check out Vengeance, Fierce, White Flood, C4, PSU etc. or Ultima, Pump-bol, RagNOrock, and Body Octane for stim free. Both RagNOrock and Body Octane both come in a stimmed and stim-free version.
The protein is fine, if...