I was on a slightly different regime (Doxyrubicin) and when I asked if I should take something for constipation the day before was told that it was best not to as things can affect you either way. I was glad I hadn't because I got the other way. You may get bad nausea from the Cyclophosmamide and if so, what they give you could make you too drowsy to drive so try to arrange someone to drive you. And if that is the case, try for something more than Maxalon to take home. If you do feel really ill at home, ring the treating centre and ask for something more - don't suffer in silence. You may be able to organise them to fax a script to a closer pharmacy (you'll need to check with the pharmacy that they're happy to do so and that they have the medication). You need to drink 2-2 1/2 L fluids for the first 3 days and if you are able to do so, go for small walks.
I learnt this from my first treatment and have managed well since - I just had my third yesterday. Good Luck