This past Saturday I went out drinking to forget about my recent breakup, and I ended up drinking quite heavily, shots and all. By the end of the night, my two guy friends ended up driving me home. They say I fell asleep in the backseat of the car. I have no memory whatsoever of what happened between the time we left the bar and the next day when I woke up in my bed (so these are approximately the hours of 4am to 2pm). I apparently got into my house at 6:30am and was walking around conscious, because my mom yelled at me for slamming doors and waking them up.
However, when I woke up Sunday my head was throbbing, and not just the hangover headache throbbing, but the actual painful, like I had hit my head hard, kind of throbbing. My collarbone and shoulders were also in pain, and it felt as if I had fell really hard or someone had beat me up. I have no memory of what happened at all. Could I have suffered a mild concussion and passed out after I had reached my house? Or is this strictly alcohol-related? I am just really worried, and wonder if I should visit the doctor to get my head checked out.

Also I don't know if this is relevant--but I have had no dreams for the past 3-4 nights, and am having trouble falling asleep. But once I do fall asleep it's like I'm knocked out and it's difficult to wake up when I have to. Any advice/help would be much appreciated.