pregnancy?

Dear Doctor, My last period came at 29 of September AND lasted about 12 days. As far as I know the period before came at the beginning of September. As soon as my last period ended, my husband AND I tried to get pregnant. In the last three days I have been suffering from very strong pains in my back AND my lower AND middle stomach [I can’t sleep AND I have heartburn {“tzaravet”- in Hebrew}]. However, I didn’t get my period yet. Today I did a home pregnancy test AND it came out negative. Did I do the test to early? What could be the cause of my pains? What is the earliest date to do another home pregnancy test? Thank you very much for your answers, have a wonderful week

you should be examined as soon as possible