Hi there! This sentence it's just in the present:)
It's Wednesday afternoon, and you still don't arrive:)
But I can see why you would get it mixed up with subjunctive, they can be almost identical most of the time.
When it comes to "tu", the verbs either in subjunctive and present are identical most of the times, unfortunatelly:/
But take a look, what it would be like if this sentence was written with "I".
Present= "Miercoles por la tarde, yo que no llego"
Subjuntive= "Miercoles por la tarde yo que no llegue"
The second sentence (in subjuntive) is wrong, because it doens't make any sense. But it's just to show you that how the verb changes:)
Liek I said, when it comes to "tu" the verb in the present tense and the subjuntivetense are almost always the same:) That's why it's easy to get them mixed up:)
I hope it was useful:)
You're very good in Spanish:)