How Do You Tell If You Have A Strep Or

How do you tell if you have a strep or cold virus causing sore throat, coughing, ear and sinus pain, or spring allergies causing in addition, burning watery eyes, and nostrils? I am taking and have doubled up generic Claritin but see only drainage improvement. I have a dose of amoycicillonSp? On hand. Would that help? It is quite an ordeal for us to get to a distant Doctor. Thanks.