I take percocet 7.5MG /325. I have had no side effect since I've started taking it. I got my prescription filled today at a different pharmacy and after taking just one pill I have tightness in my throat and I feel dizzy and feel like I'm going to pass out. Even though I got it at a different pharmacy., it looks no different from my last prescription and is from same manufacturer. Is this normal? My blood pressure is a little low . Can this cause my side effects be from that?