My guess is that a plant would cause a rash where the skin contacted the plant though didn't know that eleaegnus did this.

So I suspect that you have been bitten.

I don't know but you might want to check with your GP as some shrubs do have toxic sap.

Just wonder if it is where you may have been pricked by the spines. ?

I know I am incredibly late to this thread but wanted to add that I have similar symptoms when dealing with this. Very itchy raised spots on the skin from the pollen that covers the leaves. Quite a few kids (it is bordering a playground) complain about asthma-like symptoms