You can get anemic from heavy periods, so do talk to your doctor. Your energy can get very low and it takes a long time to recover, so don't wait.
Good lube is Silk-E. You don't sound like you have a UTI, but you are very lucky because if that was me, I would get a UTI usually. It doesn't sound like an STD, but you could have a yeast infection causing the dryness and irritation. Try treating for that and wash all your underwear in hot water with baking soda. Use pantiliners when needed. to keep clean and dry.
It sounds like you could use some lube, especially at the point where you feel like you're drying out. Please use either a water or silicon based lube. You should NOT use actual oil or anything with sugar in it. Oil can be a growing ground for nasties and it breaks down condoms, and sugar can give you a yeast infection (so avoid that flavored lube if he's giving you oral sex, and don't use it for intercourse).
You should talk to your doctor about those periods. Those sound out of the normal range. I used to get heavy periods that would last 7 days, with horrible cramping the first few days, but not to the extent you're having. Still, I was having to take 800mg of ibuprofen to deal with the pain. Ever since I started taking birth control pills, I have a 5 day period, it's lighter, and I can function without any pain killers if I have to. Some form of hormonal birth control could be the answer to your period issues, but you need to discuss it with an ob/gyn to make sure you get the right treatment for you.
Hi Smilely, Ok first if you think you have an STD get tested, clears your mind, but from what your saying you sound OK.
You could try some vitamin B6, they say this works for extra lubrication, or just get your self some sex oil, theres loads about, or do both.
And if your cycles are regular, then a couple of days before they start go on some iron tablets to help buil;d up your blood and help your strength.
Hope this helps.
Good Luck