PLEASE HELP ASAP! :( could i be experiencing early regnancy symptoms?

Two weeks ago me and my boyfriend had unprotected sex on the last day of my period. (He did c** in me for the first time in my life) About a week later i was having water like discharge for about four days it increased and decreased before it completely stopped. I am now experiencing sore breasts.(never happened before) I did have Nausea once and i sleep way too much. Could i be pregnant? Is it too early for a pregnancy test? Could the discharge be symptoms from an STD? My next period is due in eight days.