Making qadha if haidh started during a salaah time

Q:

1. My menstruation cycle is regular in the sense that I have 14 clean days, 1 day istihaza and 10 days haiz. It's the same every time. So it starts at 4.43pm. I am usually always alert about performing my asr salaah before the time of haiz starts. Unfortunately today I was unwell earlier and had to sleep and over slept and only awoke after the time of haiz began. Will this asr Salaah be considered as qaza?

2. As a saahib tartib if I make ghusl and I have only enough time to perform the fard salaah and not the qazaa. When do I read the qazaa?

Woman covering the feet in salaah

Q: Is not covering the feet below the ankles for woman against sunnah? I have severe waswasa and I found out that except for Hanafi's, others consider the feet as awrah. Are my prayers invalid as I didn't cover it after knowing about the ruling. Why do Hanafi's not consider the feet as awrah. I feel scared that my namaz isn't valid. What should I do?

Filling the gap in the saff if the muqtadi leaves during salaah

Q: There is a rule in Bahishti Zewar that it is makrooh to stand alone in a row. The person should pull a person back from the row before him. What happens to the gap formed by the exiting of the said muqtadi to fill the previous row?

If a Muqtadis wudhu breaks during prayer, should he just leave and leave a gap in the saff? What should he do in this regard?