Hi Beth & Dawn;
I don't mean to sound cruel, so please don't take it that way.  I carry an Epi-Pen Jr but have explicit instructions not to use it on my son except in a life and death situation.  Obviously if you are alone you have no choice but to use it on yourself when you feel the need.  It is my understanding, from my son's Pediatric Allergist that an Epi-Pen is not made to stop an allergic reaction, it is used as an adrenaline to keep your heart beating which the anaphylactic shock  stopped or may be stopping.  I have also had complete instructions not to use it on my son until he is at the unconscious stage.  
Has anyone else had anyone tell them this?  
Thanks for sharing what it feels like.  No one has ever shared that info with me.  I haven't ever had to use it on my son....thank goodness, but it's nice to know what I should look for or expect.