Getting back into the groove of things after having so many days off can be really hard, but it's certainly not impossible!
For starters, remember that it will take some time before you're used to being back in your routine. Even if you had the same routine for a year, breaking it can make coming back to it harder. Just be patient with yourself and allow yourself the time to adjust.
That's not to say let yourself get away with not doing things. There's a fine line between not being used to something and being lazy and therefore choosing not to do it. Don't allow yourself to get roped into the mindset that you're still on break; give yourself a week to adjust back into your routine and after that become more strict with it.
Things need to get done and if you want to be productive and continue to succeed in this new semester you have to remember how you began last semester.
It will take time to adapt your routine to you new schedule, but figure out what day you can grocery shop, do laundry, or clean, and make sure to keep doing it those days. If not, it will pile up early on and you'll be left with a lot to do all at once, and instead of having a routine set in place, you'll be forced to try and make one in the middle of having a lot of other things to get done that have piled up.
Start early, stay focused, and remind yourself of your semester goals often so that you are able to remember what those routines are set in place for.
Have a great semester!