Hmm... Here is a list of things that could have went wrong and how to fix them:
1) Pausing. Pausing too much will affect the growth pattern and slow down the growth process. If this is the case, just be patient and wait; it'll evolve into something eventually.
2) Glitchy battery. Most connection Tamas use CR032 batteries. A common glitchy battery is CR025. How to fix it? Change the battery to a CR032 battery.
3) Changing time. Changing time too much will also screw up the growth time. Just like you should do with pausing, wait patiently.
4) A normal glitch. Sometimes, Tamas just have bugs and glitches. Hit the reset button and press download. If that dosent work, take he battery out and put it back in.
5) Debugging too much. If you debug your Tama too much, it will get glitchy.
Usually, even if the age counter gets thrown off, your Tama will still evolve. Wait another day or so, and if there are no changes, try what I said above. But wait AT LEAST 24 hours.
Hope I helped
-Kero