Advice on sleep medication

Patient: Hi there,I took some diazepam at 8pm this eve and would like to know if it’s safe to take 50mg benadryl to help me sleep (It’s now midnight)? I am going through a particularly stressful time at the moment. I take no other medicine except pain killers for period pain at the moment. I’m also on birth control. (If that’s relevant). My doctor also suggested I take 3mg melatonin to help me sleep. Is it safe to take that in addition to the diazepam and benadryl? Or could I take melatonin instead of benadryl if benadryl is unsafe to take?Many thanks for your help,Roxanna