welcome to Healthcare Magic.
Your above mentioned symptoms indicate presence of depression
in your case. Having smell of rotten eggs may be due to olfactory hallucination
. In presence of olfactory hallucination, it is better to rule out pathology in brain by MRI, which is already planned in your case.
Depression can cause somatic symptoms like headache and nightmares
like having seizure. It is better to start treatment for depression under psychiatrist
Wish you all the best.
Dr Ashish Kumar Mittal