1) After saying the Bracha of HaMapil it is forbidden to talk, eat or drink, as doing so will be a Hefsek (interruption) between the Bracha of HaMapil (which is a Bracha on [going to] sleep) and sleeping, and render it a Bracha L'Vatalah (a blessing in vain)
If one knows that he/she will not fall asleep for a while, or if one wants to read a book/Sefer after saying Krias Shma Al HaMitah, it is best to say the Krias Shma without saying the Bracha of Hamapil, and only say HaMapil later on when you are ready to go to sleep.
2) If one said Krias Shma Al HaMitah and HaMapil and fell asleep, and then woke up in the middle of the night, the Krias Shma and HaMapil need not be repeated, as the obligation is only to say it once a night. (Psak of Rav Chaim Kanievsky Shlita) There are some opinions that require you to repeat the Krias Shma and HaMapil, when going back to bed in middle of the night, without Sheim Umalchus. (Magen Avraham Siman 6:8)
Halachos for Shabbos Kodesh
1) If one used the bathroom after saying HaMapil, it is permissible to say the Bracha of "Asher Yatzar", and it isn't considered a hefsek (interruption) between the Bracha and sleeping.
After saying "Asher Yatzar", one should repeat the first Parsha of Krias Shma and say some Pesukim (Shu"t Tzitz Eliezer Vol. 7 Siman 27, Shu"t Be'er Moshe Vol. 1 Siman 63 and many others. The Chazon Ish disagrees and maintains that it should not be recited, as it will be a Hefsek and render your HaMapil into a Bracha L'Vatalah. It isn't clear how the Mishna Berura paskens in this case)
2) Similarly, if one remembers after HaMapil that they didn't daven Maariv, count Sefiras HaOmer or say Kiddush Levana (if it's the last possible night for it), it may be said when remembered, and the Krias Shma and some Pesukim be repeated when going to sleep. (The Steipler Zatzal debates whether the Chazon Ish would differentiate between Maariv and Asher Yatzar or not)
QUESTION & ANSWER CORNER:
(Reader Submitted Questions of interest (on topics related to Halachos we covered, as well as other interesting topics) and my Answers taken from the Q & A page on the Halacha For Todaywebsite. For study purposes only, NOT for Psak Halacha. Questions can be sent to Halacha For Today)
Reader's Question:
I would like to make sure I understood correctly [what you wrote in the Halachos].
From what I read, [I understood that] during davening Shemone Esreh one, who lives in galus - should face Eretz Israel, one who lives in Eretz Israel - should face Jerusalem and one who lives in Jerusalem - should face Western Wall. If this is correct, should Americans face South and not Mizrach (East) [as is the common custom]?
My Answer:
Yes, you understood the Halacha correctly. The ideal direction to daven is towards Eretz Yisroel, and not necessarily towards Mizrach, as most of us commonly do!
The Rama (Siman 94:2) says that the reason "we" (meaning those in Cracow, where he resided, as well as the rest of European Jewry) daven towards Mizrach is because we reside to the west of Eretz Yisroel.."
In the USA, we are not to the west of Eretz Yisroel, and thus should not face "Mizrach" according to halacha, yet that seems to be the prevelant Minhag.
Please consult your Rav before making any personal changes regarding which direction you daven.
Our holy sages, the Chazal tell us
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן עולם הבא, שנאמר הליכות עולם לו, אל תקרי הליכות אלא הלכות - one who studies [at least two] Halachos daily is assured a portion in Olam Haba - the world to come. (:מגילה כ"ח )