Get the following tests:
Serology: Hepatitis A, B, & C
Hemoglobin A1c
Fasting glucose
The latter two are diabetes related. The Hep tests are needed for your symptoms are related and you need to rule it out. You can carry Hep C for 5, 10 or, 50 years and not know it.
See a Dermatologist about your skin issues.
As far as your anal fissue its not diabetes related but I would at least get a biopsy to see what it is, stop its growth, and rid the darn thing from your butt.
oh and i was loosing alot of weight before, actually 40 pounds, and then i couldnt loose no more, thats why i went to doc. Plus the other reasons.
your lucky your headache goes away with advil if you do have diabetes, Im a Type 2 Diabetic, when i was diagnosed i was drinking pry about 2 gallons of water a day and i was still thirsty, and because of that i was going to the bathroom every 2 hours sometimes every hour. I would get headaches that i would have to take 4 tylenol just to knock me out so that it would stop hurting, it felt like a really bad migraine but it was just the high sugars making my head hurt, cause now i rarely have a headache. I never had a yeast infection but did get chlamydia (however you spell it) which was kinda how your describing. When i had got that checked they didnt find the diabetes.. it was actually 6 months later when i went to doc and got a full work up and found out i was diabetic and had hypothyroidism. About the eating, I was actually always hungry, always wanting sweets before, or just something to munch on especially when i would get the headaches i would think its cause i wasnt eating enough especially that i would eat like a egg burrito in morning around 6 before work, and then by 9 i was feeling hungry, but its just cause my sugars were going high that it was making me want more.
Your skin gets really dry with high sugar, could be the cause of your fissure.