I've done just about every drug under the sun, except Rohypnol. It's is available IIRC in Mexico. countrybumpkin's story sounds more like Rohypnol than GHB. Rohypnol tablets are dull green with a blue core that, when dissolved in light-colored drinks, will dye the liquid blue. The drug feels like you took a Valium from what I've read, not sure if you have experience with that Don't order blue drinks!
I had a similar scare once, and it took a bit for the place to sort things out. I started eating healthy and buying stuff at nature foods ever since. Hopefully, they get it cleaned up pronto! Stay safe out there, and maybe stick to homemade meals for a bit.