EMLA cream in the UK is used mostly as a skin local anaesthetic for children prior to sticking needles into their veins. As such it's relatively benign but as with all medicines there are a very small number of people who experience side effects.
The scaremongering on the site you quote is predominantly to do with well documented cardiac side effects of local anaesthetics but you have to have quite a dose to experience this - possibly using the cream over and over again in a 24 hour period could cause issues. The usual recommendation with children is one or 2 applications per 24 hours. It also depends on existing medical conditions you may have and medicines you take.
In reality, if you've already used it then you're probably safe BUT you shouldn't really trust advice you receive from total strangers on the internet. Go and see your GP and ask her for advice. Be honest and tell her what you've tried, she will be able to advise you properly.
Incidentally, if you've rubbed it on your todger then you should tell any partner you are poking at the time, especially if OWO or BB as they may also experience side effects
