Heaviness and light contractions in pelvis

Nichola

So I'm 15 days late and I've taken 2 tests 1st one 8 days late and 2nd one 13 days late both were negative. Now I'm feeling this heaviness in my lower abdomen like my womb is contracting could I be pregnant. I'm scared to do another test, can't take the disappointment. Keep looking out for af but nothing. HELP.