Welcome to the forum, Ananda Roy Chowdhury.
iI told you?" This could be correct. We can't say for sure without more context.
"My tense is alright." It sounds a little strange. Once again, only context can tell us if it's appropriate. Many people prefer to write 'all right', and some consider 'alright' to be incorrect.
"As I had said, ......." Yet again, we need context.