Help please

I was suppose to have my last periods date on 09-12-23 but till date I couldn’t get my periods and we were planning to have pregnancy and had intercourses during the ovolation period. I am experiencing severe back pain leg pain and some times cramps. Had taken pregnancy test last week but it came negative don’t know why but these symptoms along with tiredness makes me slow everyday

Do i need to seek gynecologist help or take test again with another brand what is the solutions