Sorry, but I am not able to make out what the red patches area, you should speak to your doctor about this.
I will address your "frequent urination and burning before/after urination and pelvic pains sometimes".
These symptoms are typical of a urinary tract infection. The other reason for pelvic pains associated with urinary problems could be kidney stones.
This could also be causing your low back problem.
If you are still having these symptoms, do NOT wait for your MRI scan, but make an urgent appointment to see your doctor to get your urine checked and a blood test done to check your liver and kidney function. Whilst having the blood tests done, it would also be a good idea to get your prostate checked too.
In the meantime, even though it is uncomfortable to pee, you must drink plenty of fluids. 2 litres of water a day is usually recommended, but more if you sweat a lot.
To help ease the discomfort of burning, as a home remedy you can put in a teaspoonful of Bicarbonate of Soda into a glass of water and drink this. You can do this 3 times only with 1 hour in between each dose. This will neutralise the acidic urine that is causing you the burning sensations when you urinate.
Please, make an urgent appointment to see your doctor to get checked out for the urinary problem. You may need a antibiotic if you have an infection.
Let me know how you get on.
Best wishes.
its just looks as first stage pressure ulcer in the photo, thats why I m asking. Like you ve sat down on that area a lot
i worked hard (sit down a lot) in last 6 months. recently, not that much.
Is the area under any pressure? Are you sitting a lot in this area?