I accidentally took 160 mg of lisinopril should i be concerned?

It partially depends on what dose of lisinopril you have been taking. If you takes 80 mg daily (max dose 40 mg, twice a day), I would say the effect of total dose of 160 mg on your blood pressure will be insignificant. In general, you just have to watch for the symptoms of very low BP such as faint, lightheadedness, palpitation, drowsy, etc. Drink chicken broth + stay in bed if symptomatic.