Bad 3MMC or some kind of cross-tolerance — it's conceivable that there is receptor downregulation even if PEA isn't active in the same way due to functional selectivity
Btw ~5pm doesn't tell us much, not everyone lives in your timezone...
Definitely bad 3-MMC if you ask me. I got tachycardia from as little as ~25mg of 3-MMC.
There might be some cross-tolerance but tachyphylaxis of such a short acting substance like PEA should be over 7 hours later to at least feel some effects from a solid dose of 3-MMC.