Help! My Fantail is not pooping or eating

I need help! My 3 year old fantail who has been very healthy except for
constipation all her life, has been sitting on the bottom of the tank for the
past 2 weeks or more, too heavy to swim. I have tried giving her peas, she
has eaten them for a couple of days, but has been unable to poop anything out!
She has become very distressed and now is getting depressed. Today she would
not eat. I have been researching if there could be another problem on the
net, and I am wondering if she could be egg-bound. Her stomach is not
completely taught today but more squishy and she has two holes, her rectum
and then another one just beneath it which has a dark grey oval around it,
which I think I have read, if I am understanding correctly, is a sign that
she has eggs inside her.

I'm concerned that I am not doing enough for her and that I am not diagnosing
her condition properly. Can someone help me?? Today I gave her an epsom
bath to try to draw some fecal matter and all I got was some redness at her
anus, sort of like a sore!! which has really freaked me out!

I purchased some antibiotic food today, but she won't touch it and, usually
ravenous, she won't eat any peas today.

Do female goldfish ready to lay eggs quit eating? What do I do if she is egg-
bound? We have no fish doctors where I live. I don't want to lose her!!

Can anyone help me?????