My areola on my left breast is bigger than the right one. Can it be fixed?

Following implant removal the breasts will contract for several months.  Once the breasts stabilize then you can consider areola reduction. 

Once you are fully healed from your implant removal surgery you can consider having the areola downsized in order to improve symmetry. Speak with your surgeon who will give you an approximate time frame based on how you are healing.

Thank you for the question.  You should allow the surgery you just had to completely heal before undergoing any revisions.  It is certainly possible to achieve more symmetry from future procedures.  Good luck with everything.

You mention you "had my areola smaller." Did you have a donut mastopexy at the same time as you had your breast implants removed? You should discuss your concerns about your asymmetry with your plastic surgeon. A donut mastopexy on the larger areola can decrease the diameter, though the two sides will always have some degree of asymmetry.The timing of further surgery will be influenced by whether you just had your implants removed through the areola or if you had a donut mastopexy. Your plastic surgeon will let you know how long to wait.

Yes, it absolutely can be fixed. Very little downtime, can be done in office setting. This can be done under a local anesthesia and you can return to work or school the same day. The incision heals pencil line thin and you still have normal sensation and can breast feed.

Yes but allow at least 3 months healing phase before reoperating on that areola. This allows swelling to decrease to judge the true differences...  

Yes you can have an areolar reduction for symmetry. Please see your plastic surgeon for options as you recently had surgery and he/she may want you to recover completely from your initial surgery before going to the next.