Hi there ~
I understand your concern. Burning sensation inside penis is usually due to dehydration
and it might help to be properly hydrated during and after sex. Heartburn
can be easily treated with proton pump
inhibitors (PPIs) and avoiding food that induces gastritis. Also using digene tablets or syrup before meals can be very helpful. I also think that keeping a regular schedule in terms of your daily routine, meals and work and exercise will help with your headaches and abdominal pain
. A psychiatrist
can help with any anxiety that you may have regarding your conditions.
Take care and have a lovely day!