Half niqaabs

Q: Nowadays it has become a fashion to wear the "half niqaabs" and in this case the whole forehead is left open. So is it permissible for a woman that wears the niqaab, to show her eyebrows?

Irregular bleeding

Q: I would like to know how to work out my period as my cycle has changed. I still have the marina on. During these last few months I bled very little. For example I get a brown discharge for two days and then 14 or 15 days later I get a red discharge for two days. So basically throughout the month I'm bleeding for about four days on and off. How do I work out my period? I also get a whitish yellow discharge often. Will I count that as period blood also? This month I never bleed at all for about 22 days and then I bled for about 6 days. I'm very confused as I don't know which days to count as my period and which are my clean days. I want to keep my qadhas before Ramadan but I'm not sure on which days I should fast.