Running advice needed (3 weeks to 5K)

I have recently started jogging again and was doing the couch to 5K program. Of course, I got the perfect storm of illness, knee pain, and really busy schedule that resulted in missing out on about 2 weeks of workouts.

Prior to the break, I was doing a comfortable 1.5 miles jogging and was ready to increase. Today, I did 1.5 miles but the knees were giving ominous signs and it wasn’t exactly comfortable.

I want to do a 5K on March 12, jogging as much as possible. I have 3 weeks - how much distance and/or speed can I reasonably attempt to increase each week without too much risk of going overboard? I have 10% in my mind but I’m not sure where that figure comes from. Thanks!

Your first concern is to resolve the knee issue, you only have the one pair.

Where is the pain, both knees or one?
During run or before /after?
Sudden or gradual onset?

The general rule of thumb is to increase no more than 10% per week.