Erin,
You have to give the avonex some time to start working - it isn't instantaneous.
As for it being Sunday, doctors all have answering services and I believe you should call if the pain is this bad. I would venture the guess that you will be told to go to the ER for treatment of these symptoms.
This all very well could be related to your MS, there is no rule as to how often we experience relapses. It also could be a symptom of something else going on with your body - the only way you will know is by being seen by a doctor.
Either way, I hope you get some rest tonight. I hope the pain subsides and you can talk with your neuro about this soon.
feel better,
Lulu
o also i been taking avenox for 5 weeks in have relapsed twice in the time of taking it first one lasting for a week second one just now starting ..aint really helping much id say