Pain upon urination for 6 months+. Not always, but more and more lately. Like peeing razorblades. Not a uti, not kidney stone, not std. Ideas?

See a urologist. You should see a urologist for further testing including a cystoscopy. Possible diagnoses can include bladder cancer and interstitial cystitis.
Many things. It could be a number of the things you mentioned including interstitial cystitis, prostatitis or urethritis. It would be wise to see a urologist for further investigation of your symptoms.