Congrats on Humira, I really like the stuff myself, but the pens are very tricky at first.
Some tips ;)
1.) Let the Pen reach room temp before you inject it. Let it sit out for a good ten minutes, before you inject it. This will help a GREAT deal with the sting.
2.) Pressure; It's all about
pressure. You grab some skin, preferably some fat, push the pen hard against the skin, and hit the button on top. Keep PRESSURE hard and firm on it. I put my back up against the wall, and get in the floor, that way I don't jerk and pull the pen away. I use a leg, you can use the belly if you are ok with that, I am not.
If you jerk and move the pen away, the medicine will go all into the air, and you have a "misfire". Call up Humira, tell them about
the "misfire" they will give you a replacement pen. Consider having someone help you the first few times, and tell them to keep firm PRESSURE, don't pull back.
3.) Here is a video for you to watch.
www.humira.com/RheumatoidArthritis/AdministeringHumira/Default.aspx