its important to shock the pool for a period of time- shocking is a process, not adding chlorine once.
When you have algae, you have to get to shock levels, AND maintain those levels for a period of time.
If you add chlorine once (which it sounds like you may have done), then let it drop back down, often all the algae isn't killed and it grows back; you maintain the shock level until all the algae is cleared, and any other material in pool (organics from dying algae, etc) is cleared by filter and/or oxidation
your TA shouldn't be an issue right now- but the cloudiness and FC stability issues are indicators of incipient algae blooms...