Ugh I need opinions.

Okay so for the past week I've been extremely tired and nauseous all morning nearly to the point of getting sick, my period is not due until October 18th but I get my period every other month so that doesn't help. I've taken two of those 88¢ pregnancy tests because I had them on hand (no idea if they even work) and they both came back negative. Could I be pregnant? Like can you have morning sickness before you test positive? And no I'm not some irresponsible 12 year old btw lol.