I have been injecting Betaseron 1b since 2003. The ONLY side affects I have are the injection site reactions. Some red/purple marks lasts for months. I don't inject on my arms...ouch too much. My legs I use in the winter time but not when warmer weather is coming.....I love my shorts. Most of the time its my belly and behind which my hubby does for me. I am poka-dotted front and back!
Ice before a shot helps a little and be sure the alcohol is dry on the skin. Autoinject for me makes less a reaction mark. The better hydrated the skin, the better the shot......if you take a shower every night, this can help plump up the skin.
Good luck to you and increasing to the normal dose is the best way to go.
P.S. My brother in law has RRMS also and has been injecting betaseron for over 12 years.