Keep it up! It took me about 6 weeks before my legs didn't ache and sore almost to the touch. I jumped in at 20 miles RT on a 1977 Schwinn 3 speed. I should have thought that thru better but you start with what you have. As others have said, check how your bike fits, spin the pedals and just have fun. If you need to take a day now and then do it.

And I'll second ericy on the longer weekend rides. That would help alot.