Your signs and symptoms described reveal that you have some chronic infections in your mouth which are bothering. First of all forget about individual teeth having problem but just concentrate on improving your oral hygiene
. If there are active infections with symptoms like pain, fever
, visible pus discharge, start one course of antibiotics under the guidance of some doctor. I cannot prescribe antibiotics here because I cannot decide you one will suit you better. Next, if you dont have these active signs but just constant irritation or mild pain, start improving your oral hygiene with the help of mouthwashes or just warm salt water gargling 3 times a day (provided you are not hypertensive). The oral rinses containing hydrogen peroxide
are very good to tackle infections, so check with your pharmacy if they have one. Next step is consulting again your dentist
and starting some treatments to address these. Your weakness maybe due to lack of appetite
or inadequate nutrition. You can take some B complex vitamins
to address this. Start eating properly and if you have problem eating because of one or 2 teeth, ask your dentist to correct them. I am sure this should solve your problems. All the Best!!!