You are right that clindamycin can have nasty side effects for some. Try eating some yogurt with acidophiles in it. That helps maintain normal bowel flora.
All antibiotics take some time to work. I'm glad to hear you are getting some relief from the pain. Surgical extraction trauma can last for quite some time, too. Neighboring teeth want to naturally shift to close in the space (Something to consider unless it was a back molar).
That can stretch the periodontal ligament causing pain also.
Give yourself a couple of weeks to heal. Have you considered an implant to replace the lost tooth? They are as close to nature as dental medicine can get.
Dental work always seem to carry some depression with it. I really think that's normal. We all seem to think about the negative connotations and that somehow, it's our fault for having an infection in a tooth and that we should feel shame.
Not so. Be proud of yourself that you took care of a problem and will continue to do so. It's really no different than any other infection.
As my MIL used to say, "This too shall pass.", and you know what? It will.
Hang in there and please let us know how you are doing. It's always great to hear a success story!
My very best to you,