From Hamlet's very first appearance in the scene, all dressed in black, we can tell that the prince is none too happy. And we can infer that he is not just upset and gloomy about his father's death, but also his mother's hasty marriage tot his uncle Claudius. Listen to this exchange between mother and son (Note, the little play on the word "common," delivered as a veiled slur to his mother) :
QUEEN:
Good Hamlet, cast thy nighted color off,
And let thine eye look like a friend on Denmark.
Do not for ever with thy vailed lids
Seek for thy noble father in the dust.
Thou know'st 'tis common. All that lives must die,
Passing through nature to eternity.
HAMLET:
Ay, madam, it is common.
QUEEN:
If it be,
Why seems it so particular with thee?
HAMLET:
Seems, madam? Nay, it is. I know not seems.
'tis not alone my inky cloak, good mother,
Nor customary suits of solemn black,
Nor windy suspiration of forced breath,
No, nor the fruitful river in the eye,
Nor the dejected havior of the visage,
Together with all forms, modes, shapes of grief,
That can denote me truly. These indeed seem,
For they are actions that a man might play;
But I have that within which passeth show,
These but the trappings and the suits of woe.
Yes, we can assume he's quite upset by any number of things. Then, of course, there is this part of his soliloquy in which Hamlet really rails against his mother:
HAMLET:
...That it should come to this!
But two months dead! Nay, not so much, not two;
So excellent a king, that was, to this,
Hyperion to a satyr; so loving to my mother
That he might not beteem the winds of heaven
Visit her face too roughly. Heaven and earth!
Must I remember? Why, she would hang on him
As if increase of appetite had grown
By what it fed on; and yet, within a month—
Let me not think on't! Frailty, thy name is woman—
A little month, or ere those shoes were old
With which she follow'd my poor father's body
Like Niobe, all tears—why she, even she—
O God! a beast that wants discourse of reason
Would have mourn'd longer—married with my uncle,
My father's brother, but no more like my father
Than I to Hercules. Within a month,
Ere yet the salt of most unrighteous tears
Had left the flushing in her galled eyes,
She married. O, most wicked speed, to post
With such dexterity to incestuous sheets!
It is not, nor it cannot come to, good.
But break, my heart, for I must hold my tongue!
He spares nothing in his revulsion for what she has done. He is disgusted by her absurd choice, by her ignorance, by her sexuality, by her frailty, and by her unfathomable haste.
And in the same scene he reiterates his disdain to Horatio:
HORATIO:
My lord, I came to see your father's funeral.
HAMLET:
I prithee do not mock me, fellow student.
I think it was to see my mother's wedding.
HORATIO:
Indeed, my lord, it followed hard upon.
HAMLET:
Thrift, thrift, Horatio. The funeral baked meats(185)
Did coldly furnish forth the marriage tables.
Would I had met my dearest foe in heaven
Or ever I had seen that day, Horatio!
Oh yes, scene 2 leaves us with no doubt as to how Hamlet feels about his mother's marriage.