IMO you may be doing a bit too much too early, also stretching will help rid you of pain. Stand facing a wall with your feet two or three feet away from the wall, then slowly do a push up off the wall. You should feel a nice stretch in your Achilles tendon. Of course I'm not a Doc. but it has worked for me. Giving your body some time to recover from a hard ride will help you to be able to ride for years, consider easing off the miles.