Antibiotics

Lukas has been on an antibiotic since last Friday. I am not sure if it's working or not though. He is still pulling on his ears and he cries like he is in pain at times. I do know this could be teething though. It causes some of the same symptoms. Also he is almost out of his antibiotic. They told me to give it to him for 10 days and I am thinking tomorrow morning it will be gone. Which is only 8 days it lasted. So, I called them to see what I should do. They have yet to get back to me. I do know that immunity to antibiotics are becoming more common. I am hoping he isn't in that boat anyway. It's weird how I have never had an antibiotic until I was 23 years old and by baby has already had one at 9 almost 10 months old. Crazy! What has changed over the course of time, the quality of our environment maybe? Not sure.