Advice?

OK so my stories are not following guidelines because of dialouge punctuation but I am doing what I was taught at school. I have been give websites that 'explain' the rule only they might as well be written in Japanese!

I am 30 (Old, yeah, get over it) and my teaching was simple. Start a dialouge with a capital letter and end on a period. Tags also start with a capital. Now, I am not sure when the rule changed but it obviously has. I just can't do it and to me the comma and small case start is like asking me to spell my own name wrong! I tried it on a one shot and honestly I could have cried at just how wrong it felt to do.

Kayla (Mindfreak) has offered to read updates but that leaves everything else. It will take me forever and a day to change it to what I see as wrong so... here comes the question... Do I just delete everything and start afresh? (One story at a time) or... what? Is there even anotrher option?