Changing one's intention regarding giving something to someone

Q:

1. I have made niyyat to give someone something then later I changed my decision and thought I will not give. Is it allowed for me to change my decision after making niyyat to give to that person?

2) I have made niyyat to give a dress as charity to Zaid, then is it allowed for me to give the same dress for Umar as charity, because I found Umar is more deserving than Zaid? Can I change my decision this way? Whenever I make niyyat to give something to someone is it necessary that I give that thing to the same person I made niyyat for or I can give it to someone else whom I like?

Stray thoughts

Q: I am a Muslim girl. I want to ask you a question about how can I get rid of my evil habits and my evil thoughts. Whenever I start praying to Allah Ta'ala and remember Allah Ta'ala and my Nabi-e-Kareem (Sallallahu Alayhi Wasallam) many bad intentions come into my mind. I say many bad things which I don't want to say when I recite the name of Allah Ta'ala or use my Holy Qur'an. I am restless and don't know what to. Please help me for the sake of Allah Ta'ala.

Faskh

Q: Does a wife have grounds for Faskh if her husband does not satisfy her sexually and she found him looking at other women and he does not give her nafaqah?

Finishing sehri at the last minute following an incorrect clock

Q:

1) Zaid followed his faithful bedroom clock for many years and he used to complete eating his sehri at the last minute based on the time on this clock. He recently compared his clock with the BBC time and found it to be 3 minutes slow. Is he muqallaf of following this time and repeating his fasts considering the possibilty that the BBC or any other central bureau time may also be incorrect.