Had a bad ear infection abot 2/3 week ago had 2 lots antibiotic its now 2/3 week after and node behind ear still swollen fluctuates in size biger/small?

It's ok. The node can take months to disappear, and once enlarged, it may never disappear. Pea size is nothing to worry about. Doctors usually don't get concerned until it is larger than a grape. See your doctor to make sure it's nothing more.