I don't see a problem with either of them as in this context they both work equally well. To a certain extent it depends on who is saying it and whether it is being said or written. However, in my opinion you are more likely to hear, "...like today", which is less formal and less 'literary' and thus more commonly used..
In the example "...as I was tired", 'as' is being used instead of 'because' "I went to bed early because I was tired", and is not in a similar context to the 'as' in your question.
I emphasise that this is only an opinion, as I am a native speaker, not a teacher.