Thanks for posting your query at DoctorSpring.com
Well, at 42, you can expect some sort of hormonal fluctuations, as menopause draws near.
This could manifest as irregular cycles, erratic bleeding, dizziness, nausea etc.
Just to be sure, please take a pregnancy test.
If the same condition persists next month too, please have an internal exam, A Pap smear, a pelvic ultrasound and hormonal tests ( FSH, LH, TSH, Prolactin )
All the best
Please feel free to discuss further.