Difficult at a time of what must feel like desperate loss, but it sounds like the worst thing you can do is add to your stress by worrying about alopecia, which is itself caused by stress.
I's say - don't agonise about this shampoo or that steriod, or how much hair is falling into the sink. The most important thing is to take care of yourself. It's a nice sunny winters day - go for a long walk. Or phone friends and talk to people about what a great guy your dad was. Spend the day with a favourite book (or a crappy magazine!). Cliche I know but take a long bubble bath with candles.. basically do all the things you don't usually do because you never seem to have time. Your body is telling you to stop worrying about other things and other people - and to look after yourself for a while instead.
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