Factors that break wudhu

Making wudhu after sexual arousal

Q: I am a woman and suffer regular vaginal discharge. Sometimes after sexual arousal, I am certain that the discharge which is present is normal vaginal discharge because during arousal or sexual thoughts I didn't have any discharge nor there was climax nor any fulfillment nor any orgasm. Is wudhu sufficient to offer salaah?

Blood under one's toe nail

Q: My toe was hit by a heavy thing falling down and it caused some blood to emerge within the nail. I heard that blood on the surface was pure and I washed the toe and did not think about it. Weeks later I thought about this again when I saw the dried up blood in my nail (Note: some of the blood was within my nail so I cannot remove it, otherwise I would need to remove my nail!) and I don’t know if that counts as pure or impure. 

Food getting stuck in dental cavities

Q:

1. I have cavities in my tooth, and when I eat, food gets stuck. When I rinse my mouth or use miswak, it's still stuck. But when I brush my teeth, it easily comes out. Should I brush my teeth before I perform wudhu everytime I eat, or is it okay for the food to be stuck in the cavities?

2. Is it permissible to have dental fillings so that food doesn't get stuck, or is the filling regarded the same as stuck food? If it is permissible, is there any specific type which should be used as a filling? For example, the fillings come in gold, porcelain, a composite resin (tooth-colored fillings), and an amalgam (an alloy of mercury, silver, copper, tin and sometimes zinc).

3. Sometimes, the food eaten comes back to mouth unintentionally. When this happens, does wudhu break? What about fast?

Pimples on one's scalp

Q: I have been suffering for a while from persistent acne on my scalp. It seems nearly all the pimples on my head (and there are a lot) are filled with pus and when they pop, a lot of pus and blood comes out. They are also very sensitive and tend to pop even at a slight touch or even just by themselves.

1. Must I shower every time a pimple pops or can I pray after wiping as much blood away as I can?

2. If I check to see that a popped pimple has stopped bleeding, then I shower, do I have to recheck again after the shower to see if there is blood, or can I just get out of the shower without checking again (sometimes when I am rechecking with a tissue, this make the pimple bleed again)?

3. What if I was not aware of any popped pimples before I got into the shower, do i have to check for bleeding when I am done?

4. Also, sometimes I wipe my head and see blood on tissue but I cannot locate where the bleeding pimple is on my head, in this case can I just wait a certain amount of time, assume the pimple has stopped bleeding and shower?

5. Also, I am a woman and have long, relatively thick hair and the acne on my head is making it difficult to keep, not to mention the pimples itch so much and some are quite painful. If the acne becomes even worse, am I allowed to cut or shave my hair to make my scalp easier to treat?

6. Lastly, is there an Islamic treatment I can apply to my head for something like this.