Nickel poisoning from sucking a 5p coin?

Without even realising it last night I started sucking a couple 5p coins, and stopped after about five minutes. Don't ask me why I did it, because there is no good reason! During the night I was violently sick 3-4 times, and I've had a headache and a queasy stomach all morning. I understand some of these symptoms are those of nickel poisoning, and I'm worried I may be in serious trouble. Apparently the symptoms I've been experiencing are typical of those experienced in the first 16 hours of poisoning, although I didn't consume a coin so the amount of nickel I actually ingested must've been minute, right? Apparently after 16 hours it gets worse, so I'm just wondering what people's thoughts are on this.