I don't believe we have met before, so I am going to take this chance and say hi! :D
It is highly possible that you are not a "changeling", but you could have a faerie soul. It is not always important whether your parents are fae or not, that does not determine if YOU are fae or not.
I am going to point some things out, if only to help avoid stereotypes and classifications.
As for metal, fae are not generally affected by metal, except for iron. Iron makes a faerie highly sick, and can risk killing a faerie.
Keep in mind that not all fae are "vegetarians" by human standards. There are fae who do eat meat (and some even go as far to devour humans. D:)
I am not sure about the breaking technology part, since our fae as well as ourselves (we have faerie souls and a friend who is a changeling) have no problems using technology. Granted…I have broken quite a few computers mysteriously in my lifetime though, and for some reason some things just don't seem to work. O_O So perhaps. ^_^
However, it DOES sound like you have at least a faerie soul. ^_^ You have a lot of traits that are typical to most who have faerie souls. Changelings do not happen very often anymore, and are extremely rare cases since it is much too risky for a fae to do something that extreme without getting caught. Humans lack superstition in this day and age. :(
I hope this helps you. ^_^