Hello, I will put my nursey cap on!
Pewter is okay for most people but, as always, some will react adversely. If the findings are not silver, you can easily change these. If you are happy with earrings and want to keep them, I would recommend that you do this as a precaution before you wear them. As Meeshoo says, nickel is the mail culprit for causing irritation and swelling, bleeding etc. However, good quality manufacturers will not alloy using nickel.
Pewter feels good next to the skin, quite weighty but not over heavy. My daughter loves pewter and has quite a few pieces by a company called St. Justin. They also sell silver and bronze jewellery. The patterns are lovely, mythical, spiritual and so on. She loves the Viking pieces, she is half Swede! She also loves the Celtic pieces. I have not seen the pewter on Gems yet but will have a browse on the web.
I would say give pewter a try with Gems, after all, they have the 30 day MBG!
Inge x