A severe allegy = a hospital stay

Yesterday for lunch I decided to try something new with the boys.  I gave them peanut butter and jelly.  Our pediatician advised us to wait until 18 months because of allergies, so we did.  They all seemed to really enjoy it.

About an hour later Noah was coughing almost non-stop.  He had been running around a lot so I figured it was just asthma and got out his nebulizer.  While giving him his nebulizer he was itching his eyes a lot. A friend from church was over and noticed that they were swelling.  We realized it was from the peanut butter.  I called the Dr. right away to see if we should go in or give him Benadryl.  He said Bendryl, unless he's having trouble breathing.  I told him he was coughing and it sounded like asthma. He said to get him the Benadryl right away.  So I gave him Benadryl.  Unfortunately it didn't make him tired, it made him hyper.  It seemed to help.  After about 3 hours he started coughing again and his face was puffing up.  I called the Dr. again and he said the same thing as before.  I always feel like as a parent it is so hard to know what to do.  I hate to overreact.  So we gave him one more round of Benadryl to see how he would do.  He was no better.
We headed straight to the University of Chicago.  They took us right in and soon he was getting hives all over.  They agreed that it was a tough call, but we made the right decision. They gave him more Benadryl and a shot of epinepherine.  It made him crazy!  He was like a mad man running around the room.  :)  It helped though. We got the last room in the hospital so they could observe him.  Hopefully after a long, mostly sleepless night he does well all morning and we can go home.  He still needs constant Benadryl.  He will also go home with an epipen because the allergy is considered severe.  We also have to follow up with an allergist.
We've learned a lot already.  I didn't realize an allergy could be delayed and continue to get worse.  I didn't realize coughing could be a sign of a serious reaction.  I feel very uninformed.  We have a lot to learn!  For now we're just very thankful he is okay.