hello doctor i took clomid this month. my first period was on 19th october..i had a positive OPK on 4th November..and yesterday, i noticed spotting (brownish cm).. i thought that was the start of my period but until now, nothing came. not even a dot of blood . so i went to see a doctor and he showed my 14mm endometrial lining. which is, according to him, was quite thick..my question is, how can i know that i m pregnant or will be having my period by only knowing the thickness of my endo lining?