I am also a student, but I have been giving remedies to people prescribed by the homeopaths online, as there are very few homeopaths in Japan and nobody has an access to a homeopath "live" so to say, and from my experience, also from my personal experience of taking remedies while breastfeeding both of my own children, I have to say that one dose of a 30 C remedy - unless you are very sensitive to remedies? - is not going to do much harm, well, strictly speaking it cannot do any harm at all, but might "wake up" some "dormant" unpleasant symptoms with which you might have to deal later, but after one dose this should not be a very big problem, the important point is to wait long enough after the dose, at least 2 weeks or so, to be sure that it has done all it can. Concerning the baby, I received a true coctail of remedies in France, as I did not know about homeopathy much at that time and went to a wrong person, and as I was breastfeeding all the remedies went to my daughter - but now that I think of it, after 2 months she had better sleep and was much more joyful, so she must have benefitted from what we had. The second child developped a terrible rash after my remedies, so we had to give him some constitutional treatment, but he responded very well and now there is almost nothing left of eczema and a lot of energy instead and otherwise he's a very smart and easy to deal with, even compared to my daughter, so again I did not see any reaction that would be really adverse.
So I personally would take just one dose dry and wait for 3 weeks, or even a month before taking anything else.
Carcinosin is just another remedy after it has been potentised and should be prescribed according to the symptom pictures, I here use Helios "Carcinosin", but I have heard that some people need to have other variants of the remedy, but to know if this is the case you should first try out some one type.
So, please, consider all pro's and con's and I hope you will find my experience useful.