Well, not sure what "errands" and "To Do's" you have going on, so can't really offer a decent solution. Being a home body, I do my best to consolidate any errands.
For me, I tend to make one errand trip a week and this coincides with the trip to the grocery store and is usually on a Tuesday. I find that the store is not very busy and they are relatively well stocked. Since I know that I go to the store on Tuesday, then I have a good 6 days to figure out if there are other places I need to go and I consolidate them. If for whatever reason I can't get something done on "grocery day" then I try to maximize the "retiree drive time" (between 10AM and 2 PM). This makes sure that there aren't too many people on the road and getting appointments is usually pretty easy.
As far as "to do" lists go, I just prioritize things. If it's REALLY important, I just do it. If it's not, then...well, I will get to it. If I fart around long enough, the DW will put it in the HIGH PRIORITY list and it will get done pretty quick.
As to the OP, I think some of your issue is that you are still new to the ER world. It took me about a year to get into a "routine" and you may see an improvement in how you get things done when you establish this. It's difficult to go from a w*rking world with deadlines and assclowns breathing down your neck to...well, not dealing with that BS. So, relax, it will all come soon enough.