Ramadhaan & Fasting

Q: What is the shar'ee ruling regarding the last time one is allowed to eat sehri? Are you supposed to stop as soon as the time finishes or can you finish the food you were eating during or after the Azaan? 

Q: If a child did the sahur and made the intention of fasting and later on wants to break it during the day, is there a time limit or can it be done at any time?

Q: Is their a kaffara if you break a qaza of a nafli saum?

Q: Please can you confirm does a blood test break the fast?

Q: Is it permissible to use things like lip ice, Vaseline on your lips when you are fasting?

Q: If a man ejaculates in the state of fast with the help of his thighs or a pillow or a bed etc but does not uses his hands, is his fast broken?

Q: I read on Islamiqa that a kaffara is only due on a broken fast, if the fast was broken due to sexual intercourse, there is no need for kaffara. If the fast was broken due to delebretly eating or drinking, only qadha is necessary. Is this right?

Q: I am a diabetic and insulin dependant. I am fasting and my sugar levels have dropped below 4. Is it permissible for me to break my fast or do I continue fasting? What is the punishment for breaking my fast?

Q: This morning before sehri I began vomitting. After then reading my niyyat for fasting I vomitted again a mouthful of liquid water and the again (but not a mouthful). Is my fast broken?

Q: I am 30 years old this year and its been only 3 years or so that I have started fasting, but I have not still kept those that I missed for menstruations. I would like to know what should I do? I am very guilty and feel very bad about it. I have made tauba not to miss fasts again. But what can I do about my past? Same about salaah?