I have 3 kids healthy been trying for over 2 years and haven't able to get pregnant

Feel sad anxiety 2.5 years trying to get pregnant of course not every month since my husband lives out of the states but I only travel when I am fertilize we haven't been able to conceive I have 3 kids already he has none again oovulate as per the calendar 12 iam supposed to get my period in six days I am cramping very mild some white creamisb discharge afte sexual Intercouse never seen that much before I don't knw what to expect this time scare that it will again be a fail