You will most likely puke it all out if you don't use antiemetics. Also if you don't fast beforehand and get the dosage right, it will be slow and probably quite uncomfortable/painful. If you don't plan when and where, somebody might find you and SN poisoning is easily reversible once diagnosed if they find you soon enough and\or you haven't ingested the necessary amount. Not to mention all of this can go very wrong unless what you have is not SN or it is a lower purity batch.
I am going through the same process. Way too depressed to even get up and brush my teeth. Take your time, I know how desperate it feels but slow down, make sure this is what you want and if it is, make sure you plan ahead to cover the things you need for success. Don't act on impulse.