I installed a oil pressure gauge for this exact reason. I would definitely check your oil level. Like scotty stated, the stock gauge only kicks on at 6 psi. So don't trust it, and also like he stated, how long has it been doing that?
As for seizing, if the pump is bad, it'll seize up for sure, if its from low to no oil, your timing chain tensioners could fail, bearings could scorch/break, rods could snap..etc...etc....
2000 Mustang GT-Former giggle gas addict
1990 Mustang GT w/ Vortech V3
***resident gun idiot***