Megan sick again

Since Megan joined her playgroup, she got sick a lot. Whether just common cold, flu, cough or some common infection.
Last Sunday, she woke up cried, holding her stomach and said pooo, I thought she want to poo, but no poo came out, but she farted a lot. she refused to drink milk, seem very uncomfortable and worse,she can't poo. Every times her tummy ache, she tense all over and cried. My poor little Megan.
My aunt, a general practitioner, came over and suggested me to gave her a quarter of Mylanta. she said she was ok, accept some indigestion. Yes, it helped a lot. She become more relax and eager to eat a bit.
But on Monday, she got fever. She became cranky and clingy to me. I can't do my work and my design just nursing her. I thought maybe she's teething, so I just gave her Panadol for kids. But I was wrong. Her temperature up every time the med wear off and on Thursday, I took her to her pediatrician.
Doctor said she got some infection, nothing to worried about and precribed her some antibiotic.
Well, I'm glad she's OK now but I hate the idea of giving my baby antibiotic every time she got sick. It's chemical and I don't like too much chemical ....and why seem that now the disease is so stubborn and only antibiotic can get rid of them? Or maybe you can share with me some natural remedies that I can use next time Megan got sick? TQ...