Think i took advair 350/50 earlier tonite, and just took it half an hour ago. will this cause a problem? took diltazem 120 mg at 7:45 bpis ok

No: This one time extra dose would not effect you adversely. You should be fine. Be sure to rinse your mouth after each dose.

Unlikely: Unlikely to cause problems in a one-time occurrence, but it is not recommended to use it this way. Excess of the salmeterol component, (the larger of the 2 numbers) may cause some increased heart rate and raise blood pressure, but you have said that your pressure is ok. Btw, i suspect you may really be using a 250/50 formulation.