I had a minor meniscus injury last year and couldn't walk properly for about 2 weeks, the knee was swollen and I couldn't bend it much. I rested completely during this time, the injury happened when cycling rather than running so I avoided the bike. Once the pain had gone (2 weeks) I started running again with no ill effects.
I'm very injury prone so in your situation I would probably rest for a week and see how I felt after that. This year I tore my soleus muscle but continued to run on it (it took a while to get an accurate diagnosis) that ended up taking 12 weeks to heal. Maybe if I'd just taken a week off earlier it might've been better.
Hi Helen, are you sure it's early menopause? Earlier this year my running became crap despite training, I had some rather unpleasant hormone related symptoms and self diagnosed an early menopause. Things got worse and I saw my GP and she diagnosed something else entirely, at 41 she thought I was too young for menopausal symptoms. Like Screama says ask your doctor.