"Том устал"="Tom has got tired"="Tom had got tired" literally (устал is a perfective verb in Past). Past Perfect and Present Perfect are rendered the same way in Russian as a Perfective in Past, so you don't know if it's finished right now or long ago.
However, English has its own common way to express the fatigue: "Tom is tired"="Том уставший", "Tom was tired"="Том был уставший" (past participle from "уставать"). It is a more special way to say in Russian, like to say "Tom tires" in English.
A problem English-speakers have with this sentence is the use of очень. In American English, we never use "very" as a verbal adverb - it's an adjectival adverb which intensifies adjectives. In English, "very" would transform "tired" from a verb into a predicate adjective - leaving the English sentence without a verb ("Tom very tired." needs a linking verb like "is/was".) That makes it difficult to understand exactly how очень устал functions.