What a relief. After a long night at Shaarei Tzedek they finally kicked me out this afternoon. I feel fine, though my arm still looks horrific.
For those who want the medical info: When I first got to hospital last night, the doctors thought that the antibiotics weren't given a proper chance to work and they put me on a higher dosage via IV. But then they finally decided that since I didn't have any fever or anything beyond nausea, there was no cellulitis infection. Instead, the spreading swelling and discoloration on my arm is simply my body reacting to the venom of whatever bit me. Accordingly, there is no point to antibiotics. It's now spreading away from my lymph channels and shoulder and toward my hand, which they decided was fine. Eventually hopefully it will just disappear.
As to what bit me - it's a bit of a mystery. It could not have been a snake, since it is absurd to propose that a snake bit me on my arm without my noticing. It was not a scorpion, since there were twin punctures. Some sort of spider is the best candidate. The two spiders in Israel with a severe bite are the Mediterranean black widow and the Mediterranean recluse. The latter's bite looks very different. The black widow does two puncture holes, but I think that my holes are a little far apart. Also, I had none of the usual symptoms of a black widow bite. It's an enigma!
But there's something that I must reiterate, since they even brought it up in the ER:
IT WAS NOT ANYTHING AT THE MUSEUM! We do not keep any seriously venomous reptiles or invertebrates. Because any zoo that claims that they have never had any escapes is lying!
Thanks to everyone for their good wishes!