OK, here are some answers:
1. excessive masturbation doesn't damage your sperm count in any way, the only physical damage is minor scratches on your penis that can be avoided by using lubricant. The damage that might happened as a result is you doing this instead of other things in life, like hanging out with people or working.
2. There is no normal or healthy number of times for masturbation, different people have different needs, also, n different times in life we have different needs. Some people masturbate everyday, some several times a day and some not at all. The point is that you should do what feels good to you.
3. most women get pregnant somewhere between the 8th day to the 16 day after their period. however, if you are having sex with a woman, don't count on that - use a condom, a lot of women don't count the days right, also some of them have different ovulation cycle. in principle a woman can get pregnant even when she is on her period.
Also, a condom protect you from STDs.
4. Women, just like men are different from one another, some show their orgasms really bluntly (noises, motions and saying "I'm going to come, I'm going to come") and some are quite. Some don't have orgasms at all. The only way to know for sure is ask. Also, when you have been with the same women for a while and if you take care to notice her and her reactions, while you are having sex, you'll know.