Started on Levaquin 500 mg five days ago for a sinus infection an...

Started on Levaquin 500 mg five days ago for a sinus infection and suffered severe cramps in my back after on it for less than 12 hrs. The cramps have fortunately largely abated by now, but last night I woke up with acid reflux and decided to take OTC Prilosec for it. An hour later I experienced the most vivid and horrific nightmares of my life! I couldn't get out of them and they felt like waking hallucinations. Would be interested in whether anyone else has experienced nightmares with Levaquin alone, or in combination with other drugs like Prilosec.