I think I might have a shellfish allergy.  About a month ago my husband, kids, and I went to a seafood resturant and we had oysters, crab, scallopes, and shrimp.  I was fine after I ate it but about 3 hours later I began to feel really weird.  My chest started to hurt and tighten, I felt short of breath, I had this funny tingling sensation all over my body, my heart started racing and I got really light headed.  I called the paramedics and they said it could be a shellfish allergy but because the symtoms took so long to present themselves they really weren't sure.  So they told me to relax for a few minutes but at the time there were at the house they couldn't find anything wrong. Before they left,they told me to go to the hospital if the symtoms came back.  Surely about an hour later I was on my way to the hospital.  I was wondering if it could take that long for a reation to start or was that something else?  If someone has any information please let me know.