The blood pressure change due to your climax is likely what triggered the headache. This would cause you to feel pain and burning in your ears.
its very normal to get headaches because the climax(orgasm) can create them due to hormones released. Read that in COSOM just yesterday.
Is it possible to get cravings at three months
Never heard of burning of the ears, but migrains yes. Your more prone to headaches during pregnancy because of your body going through changes.