Lorazepam and late period.

I have regular cycles and never been late more than 4 days. I took Lorazepam for only 1 day (2-3 wks ago) and now my period is 8 days late. I did a test 3 days ago and it was negative. Also this month has been really stressful and haven't had much sleep. Could the medicine cause the late period? My husband and I been ttc for 3 years.Should I consider doing a blood test next week? Thank you