A few things. First - good job on coming here early. Being a sophomore, you have a lot of time to fix your problems before you graduate. That being said, I personally don't see why you need to graduate early other than you want to get into medical school faster. If you have the time and financial capabilities, take your time and take your premed reqs at Berkeley because the other commentators are right - if you can't succeed in a premed req at Berkeley due to difficulty how can you handle medical school?
I understand you have a bad GPA but Medical schools reward reinvention. You mess up and get a bad GPA? Okay, then recognize your problems and FIX IT. Maybe easier said than done but you can do it. And if not, maybe you don't really want to be a doctor. And that's not me saying it to chide you but trying to make you be realistic. Do you really want to be a doctor? If so are you willing to put the time and effort in to fix your problems and get that GPA it takes to get into medical school.
You're a long time away from considering post-baccs. Maybe you continue your path and then your 4th year your passion finally strikes (that's honestly what happened to me) but if you can, try to fix it now before the damage becomes worse. I believe in you! Now go re-evaluate yourself and if you need to cut back on extracurriculars and focus on schoolwork because 50% of your medical school app is GPA and MCAT so definitely work on those 1st and THEN get the clinical hours, volunteer hours, shadowing, leadership, etc!