I think it is possible to use present perfect in the context because we use simple past and present perfect for adverbials today , this morning etc. **I have met my friend today.** **I met my friend today** Both the sentences are correct. So,I think both present perfect and simple past are correct. >**I have turned off the light before leaving this morning** >**I turned off the light before leaving this morning**. I think the above two sentences are correct. Besides, the OP is saying that he was speaking this morning.