hello and welcome to hcm,
as for some patients, antibiotic causes cramps in the stomach and disturbance in the routine process of bowel movements leading to diarrhea
take one ranitidine
tab along with the course of antibiotics, you will be good.
for the liquid coming out from extraction site, the reason, may be you have irritated the site with tongue, finger or toothbrush.
do warm saline gargles and do not touch the area.
if the problem persist, then visit the dentist