Hello- I am sorry to hear that you have had these feelings. I believe that you are still in the grieving process in the loss of your husband and the funeral of your neighbor was too much too soon. Your physical and emotional reaction is nothing to worry about and would be typical under the circumstances.
The best medicine for grief is talking to others and especially those who have been through the process. Try not to isolate yourself and if you feel your physical symptoms getting worse, contact your doctor.
I wish you the very best at this difficult time and if there is anything else I can do to help, please ask.