Double or Nothing; Bio/Nursing Major

I have been flip flopping on whether or not I am cut out for med school for since my first semester, (Im now a sophomore). I look some of the nursing pre-reqs; soc, pych, anatomy. However I got pulled on the hype train of pre-med with my friends. So instead of taking micro, physi, and stats. I finished my chem sequence, took bio, and calculus. This semester I am still on the pre-med (microbiology) track in that I took zoo, bot and my second calc class. I really liked the fact I had a back up plan when I was doing nursing, but now I feel that I don't have a back up plan. Sure I could work as an ER tech with my EMT and phlebotomy certs, but I really don't want to get out of college and wasted my degree. To sum up; would being a super senior (4.5-5 years) instead of 4 be worth it, or should I just go for micro and take some extra classes( get an Associates in Nursing) to get into a masters program for nursing. Cheers!