Strange looking sores are appearing at the back of my mouth after dental treatment

I lost a filling back in July, there was no pain or discomfort at all, it was a very old filling, s I decided to get a new filling, I went to a dentist I had been to before, the did the Filling and charged me £165.00, I must admit I was shocked that the prices had skyrocketed. Within about 2 weeks, I had real pain, it was so strong I would hold my mouth and rock myself, I had to take painkillers, I then decided to go to another dentist for a second opinion, He X-Rayed my mouth and then showed me on the screen, that I had a gum infection, and put me on Amoxicillin tablets, 7 days later I was pain-free. I thought that it was all over, but now 8 weeks later, I am now suffering from a Tongue problem, I now have some strange looking sores appearing, at the back of my mouth, on the one side, They look a lot like a small bubble with a bit of blood in, but not painful, I just cannot bring myself to go back to the original dentist, I have honestly lost trust and spent over £200.00 so far getting advice and the infection that was given to me by the dentist. Now my tongue seems to have an infection still! I had no pain or discomfort till I went to the dentist, this is insanity. I do not want to step inside a dentist practice ever again,

I'm sorry to hear about your distressing experience. Dental issues can be both physically and emotionally taxing.

To address your immediate concerns:

Infection: While it's possible that an infection was introduced during a dental procedure, it's also quite common for bacteria to enter an open area (like where a filling was placed) and cause an infection. This isn't necessarily the dentist's fault.
Oral Lesions: There are numerous potential causes for oral lesions or sores, ranging from minor issues like trauma or biting one's cheek, to infections, to more serious conditions. If these don't resolve on their own or if you notice them worsening, you should seek medical advice.
Trust in Healthcare: It's essential to have trust in your healthcare providers. If you've lost faith in one dentist, consider seeking a different one for a second opinion or for future dental work. There are many highly competent dentists out there who may be able to help you feel more comfortable and confident in your care.
Communication: If you ever feel unsure or concerned about a treatment plan or the costs associated with dental care, it's okay to voice those concerns to the dentist or their staff. They should be able to explain procedures, potential risks, and costs to you clearly.
Continuing Care: While it's understandable to feel apprehensive about returning to a dentist, neglecting dental health can lead to more severe issues down the line. It might be worth considering finding a new dentist who comes highly recommended and discussing your previous experiences with them, so they are aware of your concerns and can address them directly.