Although there is always some risk involved with general anesthesia
, now a days that risk is very very small. Also, the test you are having are pretty quickly done, so you will not need to be under for very long. The smaller dose of anesthesia you will need, and the short period you will need it, greatly reduces the already small risk associated with general anesthesia. Just try not to think about it too much from now until the 7th. I know this is easier said than done, but you will be fine.