Welcome to Just Answer.
Sorry to hear about your problem.
Sounds like a partial clog in the drain line.
You can use a plunger, but you will need to find a way to plug the second sink, so that the plunger can get good suction.
Second option is to remove the trap to clean it and you can snake the drain line at the same time or better yet, use a product called the "Drain King," found at your local home improvement store or hardware store; they work great at unclogging drains. It comes in different sizes for different drain diameters and you simply attach it to a hose and slide the hose down the drain pipe or at removed trap, as far as it will go. You then turn on the hose and it builds up pressure to the point where it releases in several bursts, expanding and contracting. You can clear one obstruction and then push the hose further to get to others and they are only around 10 to 15 dollars.
In addition, the disposal may have some things in it, that may be restricting the drain. You cannot always see this stuff, because it clings to the outer walls of the disposal. Plunging the sink/ disposal for a minute usually helps. Next, throw in some ice and let the disposal run. Do this a few times and the ice will help break up any remaining debris.
Chemicals often do more harm than good so stay away from them.
In the future, avoid putting in your disposal: potatato peels, banana peels, and anything else that can become slimy and stick to the sides like glue; these are the leading causes to slow draining disposals.
If you need further help or clarification on this answer, please do not hesitate to reply to this post.
Thanks for asking your question at Just Answer.
Best of Luck, Brian
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