Faraaidh and Sunnats of ghusal

Q: After mani comes out, do you have to pass urine before ghusl?

Q: Does a few miniscule grains of iron dust (grains are less that 0,5mm) affect the validity of the ghusl or wudhu? Such grains are mostly on ironware like housekeys or after doing some ironwork a few stay on the hands even after washing. You can notice them best if you hold your hands against the sunshine then you see them blinking. Few days after ghusl I notiticed few such miniscule iron grains, you can hardly notice them unless light falls on them so that they blink. The grains are less than 0,5 mm. Seems to me that they are kind of unavoidable especially when walking barefeet on floors etc.

Q: I have a question regarding ghusl. I get constant doubts about the validity of my ghusl. If someone performs ghusl and then sleeps and then does salaah at night but at night time they get a doubt that if the eye and eyebrow was properly washed in ghusl or if it was accidently left dry (note this is more based on doubt rather than certainty). The person then goes to the bathroom and washes his eye and eyebrow with the niyyah of completing the ghusl. Is this valid and he does not need have to repeat his ghusl?  If one hesitates to wash it due to waswasah or because he isn't sure, does he become napak again?

Q: One does ghusl and goes to sleep. Then one awakes and takes wudhu and puts on his khuffs. Then his wudhu gets broken. Then one finds out that there was a solid substance in the cave of his tooth. Does he only needs to remove it and wash the place? Is his masah still valid i.e. can he take wudhu with making masah over the khuffs?

Q: 

1. A person begins fasting in the state of janaabat. Regarding ghusl in this state, is the ghusl valid if the water does not reach the inside of the throat or the inside of the nose (i.e. these actions cannot be exaggerated out of fear of the fast breaking)? Will the ghusl be valid if the water did not reach deep into these areas? Or would the person make ghusl washing the nose and mouth as in wudhu and upon breaking the fast would the person then gargle the throat and wash the inside of the nose properly?
2. A person forgets that they are fasting, and thus gargles and washes the nose intensely so that water is accidentally swallowed. Is the fast broken, bearing in mind that the person forgot that s/he was fasting?

Q: Is it necessary to remove surma and kaajal from the eyes when taking a ghusl?

Q: During ghusal I doubted that some shell of popcorn is left between my teeth and gum. I tried hard to remove it with help of brush but could not succeed so I left it by considering it as my doubt and I performed all my prayers but in the night pieces came out. Now what should I do?

Q: Is permissable for a lady to not wash her hair for ghusal-e-janabah at fajr time and just make masah if it is very cold or if she gets headaches when washing her hair or if she is sick?

Q: If a person has a tattoo which is into his skin,will his ghusl be valid?