If your on antibioctics,can you get strep throat?

i dont know if i have strep throat or not, but my friend just got strep throat abotu a week ago, and now shes on antibioctics, (amoxacilin) idk if i have strep throat, i had a fever on saturday, and my throat kidna hurt when i swallowed. i gargled with warm salt water 2 times a day till now. my throat doesnt hurt as much, i returned to school today, do i have strep throat? my friends throat is sore now and could she have have got it?