You cannot bet banned for 'being bad', however, it is worth noting that staying alive as a tank relies on 2 people, the tank and the healer, as long as they work together, things will be fine.

General tips are to spread out your cooldowns, do not dump them all in one go and you can use your weaker mits as the packs get smaller.

However, without knowing which tank you play or exactly how you are managing the pulls, it is going to be harder to give specific advice.