I've never been actually yelled at, but I'm pretty sure he came close today....I could tell he was really holding back. Over the summer he went to Europe for a month, and me and another tech had to do 12 head cannula surgeries. Well, I had only done 1 practice surgery >2 months prior, and was really nervous and couldn't figure out why he wanted me to do so many (he specifically said he wanted me to do 6...) I know he wanted me to get the practice, but after only having 1 real practice surgery waaaaay before these surgeries this whole fiasco might be a little bit his fault too...anyway today, after 10 days self admin, 10 days abst, 10 days alternate environment (which is such a pain in the butt!), all done by me, we tried to inject these rats with drug to see it's effects on extinction. Well 1 of my guys' head caps popped off when we were trying to unscrew the dummies....1 guys dummies wouldn't unscrew at all, and 2 guys for some reason only got the injection in 1 side, the other didn't work. I thought his head was going to explode....I felt like it was all my fault, but I don't think it was really a good idea to have me do 6/12 surgeries for the real deal with only 1 practice (which went well but still, we just sacrificed afterward and didn't check the dummy situation), especially when it was >2 months beforehand. I feel horrible....