I feel so depressed

I dont even know were to start. I am 41 male who cheated on my wife with a sex worker I only had oral sex and couldent even get a full erection cause I knew I was doing something I shouldent be doing. This happened 2 months ago I was tested for all types of std and all came back negative but I kept insisting and and my Dr gave me a bunch of antibiotics. Even though I have tested negative for HIV at 10 weeks I cant get my mind around the fact that It is negative. I have had muscle pain and just last night I got a pea size bump behind my ear I have had Diareah for almost 2 months and my Dr. cant find the reason. I feel sick Im so scared for my family I have 3 small children that my wife can not handle by herself. If I am sick I dont know what I would do I would loose it all. I have no one I can talk to and I cant tell my wife she would kick me out and could not handle being away from my little ones they are my life I feel like Im going to snap.I have this feeling of doom I wish I would not have done what I did. I have failed my family.

[MMahon]

It sounds like you developed a problem with anxiety brought on by your sexual misconduct.
This is actually very common among many anxiety sufferers who develop all kinds of health related worries that escalate to obsessive levels of fear and worry beyond what is called for.
Your stress is understandable and your reaction is normal under the circumstances to a certain degree.  BUT your anxiety levels have brought you to the place you now find yourself.
Anxiety is controlling you and bringing you the illness you are experiencing.
There are a number of things you can do to help find relief.
Seek counseling from a counselor/therapist/psychologist trained in marital infidelity and anxiety disorders.  
Seek spiritual guidance if you are a person with religious beliefs.
Tell your wife what happened and how you feel and what it's doing to you.  I know this is the hard one to do but I think it's the key to your return to 'normalcy'.   You've betrayed your wife and you know it and your body is punishing you for it. Admitting your infidelity, taking your punishment, whatever that may be,  and finally proving to yourself and your loved ones that it won't happen again, is good medicine in my opinion.  
We all make mistakes and frequently they are serious ones.  Things won't go back to the way they were before, we can't change the past.  But you can change the future and become a better person for it, admitting your shortcomings and becoming a better person as a result.
I believe there is another forum here on medhelp dealing with your concerns.

[cheshchesh819]

and that is all that iswrong with you guilt,you have cheated on your wife and cant tell a soul,so it is eating you up inside,so you are having all these symptoms,knowledge yourself you cannot get aids unless you have sex with someone,and whilst you are there knowledge this fact you have a wife and three kids who you say are your life so in future think before you act,because it aint just your health you put at risk when you cheat,its your wifes and then your children would suffer.Are there any problems in your marriage that might need looking at