Srinagar to Pahalgam is 2 hours distance. Srinagar to Sonmarg is 2 hours of distance Srinagar to Gulmarg is 1 hour of distance. Yes you can cover each place for a day from Srinagar and return back. You can cover most important places in these spots. Coming to your other option from Amritsar you can book a cab and cover the above two places mentioned and return back. My suggestion would be Srinagar and other spots for three days along with your fix plan. Since the weather will be cold with snow kindly carry all necessary winter wears.