Weeks I have been suffering with hives .. But today I was sitting on couch when suddenly I started…

Weeks I have been suffering with hives .. But today I was sitting on couch when suddenly I started coughing , lost my breath and keep feeling tight in chest .. I know that allergic reaction ..I just don't know what's going on ! I never suffered from this .. Took a benadryl quick and trying to relax still alight trouble breathing ..