Passing wind in the Musjid

Q: I sat in i'tikaaf this year alhumdulillah. But my question is approximately every 15-20 minutes I needed to past wind (due to digestive problems). It was very hard for me to pray taraweeh and the other salaahs but Alhumdulillah I managed. So will I get sin for passing wind in masjid?

Masturbation

Q: I am a 15 year old Muslim boy. My question is that is masturbation also not allowed for teenagers who are not married. With all due respect I do not go against Quran and Hadith but this topic isn't mentioned in it specifically. I mean if masturbation stops us from zina and watching porn before marriage shouldn't it be allowed for the unmarried?

Waiting for one's companions to perform Salaah in jamaat when travelling

Q: I would like to know the usool/adaab when travelling in a group and stop for salaah at a musjid where the salaah is almost finished. All the brothers in the group have wudhu but one brother doesn't have wudhu. Should all the brothers with wudhu join the jamaat leaving the one brother to miss salaah with jamaat, or should all wait for the brother making wudhu and perform another jamaat, or should most join the main jamaat and a few wait for the brother making wudhu and make another jamaat?

Getting married to an acquaintance from school

Q: I plan on making nikaah next weekend and need to know if its allowed. This man and I have known each other since school but I married another. That marriage didn't work and I've been divorced for 5 years. I have twin sons (13 years). My school friend and I have now reunited and plan on making nikaah. He has daughters in their teens who live with him.

1. Is nikah allowed?

2. Can our children live together?

3. We heard a man is not allowed to marry a girl from his past. Is this true? We had no relation back than. We were just teens.

Haraam relationship

Q: I want to discus my friend’s problem. She loved a guy truly. She even on his demand exchanged body pictures. Now her boyfriend wants her to leave him. She came to know his reality that he was just using her. After that she repented a lot about exchanging pictures. She cries every night and asks Allah for forgives. That boy is now telling her that he didn't see any pictures and she may move on and select a better guy for marriage but in real he saw every picture. Now according to Islam should she leave that boy or repent whole life and don't marry anyone else or should she ask that boy to marry her? She is very worried. She even thinks about suicide. Please help. What is the solution now?