I have been really scared because early in the morning around 3-4 am, I got a dream of prophet Muhammad!I was clearly able to see his face! He wore some blue robe like old Saudi Arabians! That man told me that"I am prophet Muhammad! I'm the messenger of God! I will save you from the hardships and pain you undergo! "And he told,"La ilaha ilah'allah Muhammadun Rasulullah"and I also repeated the same! And immediately out of fear I woke up! That man had a long face! Not too tall or short! He was of medium height! His complexion was wheatish brown! Not too fair and and too dark! In the middle of it! He had broad shoulders! He had round eyes! Had long black beard! He looked not too old! He had a book in his hand! Looked like Quran and he had a bright light around him! I am a Hindu girl! What does a Muslim prophet has to do with me?! I'm really scared! When I enquired about it to another Muslim he said it is rare for prophet Muhammad to come in one's dreams! And devil cannot take his forms in dreams! So is that really prophet Muhammad and does he talk to a Hindu girl?!
Your inquiry has no clear answer, I'd say it is more about your reaction about it.
As for the facts there' actually is a sahih (sound) narration or prophetic tradition saying:
Messenger of Allah (ﷺ) said, "He who sees me in his dream will see me in his wakefulness (or he (ﷺ) may have said it is as though he has seen me in a state of wakefulness), for Satan (the devil) does not appear in my form." (Riyad as-Saleheen)
But some scholars say that this primarily -if not exclusively- applies for the sahaba () the companions of the prophet () as only they could recognize Muhammad () truly as they saw him and therefore seeing him for any later generation is considered as a doubtful matter, for further details refer for example to Fatwa islamqa #23367 which seems to hold the opinion that it is possible for later generation. However it could be possible or couldn't be rejected and taken as a kind of inspiration, warning or what ever may lead a person to wake up from his/ her earlier life and misdeeds.
So far the explanation of the statement of your Muslim friend.
As for the description of Muhammad () in some sound ahadith (prophetic traditions):
Allah's Messenger (ﷺ) was the handsomest of all the people, and had the best appearance. He was neither very tall nor short. (Sahih al-Bukhari)
I heard Anas bin Malik describing the Prophet (ﷺ) saying, "He was of medium height amongst the people, neither tall nor short; he had a rosy color, neither absolutely white nor deep brown; his hair was neither completely curly nor quite lank. Divine Inspiration was revealed to him when he was forty years old. He stayed ten years in Mecca receiving the Divine Inspiration, and stayed in Medina for ten more years. When he expired, he had scarcely twenty white hairs in his head and beard." Rabi`a said, "I saw some of his hairs and it was red. When I asked about that, I was told that it turned red because of scent. " (Sahih al-Bukhari)
Jabir b. Samura reported that Allah's Messenger (ﷺ) had a broad face with reddish (wide) eyes, and lean heels. Shu'ba reported:
I said to Simak: What does this dali-ul-fam mean? And he said: This means broad face. I said: What does this ashkal mean? He said: Long in the slit of the eye. I said: What is this manhus-ul-aqibain? He said: It implies little flesh at the heels. (Sahih Muslim)
The Prophet (ﷺ) was of moderate height having broad shoulders (long) hair reaching his ear-lobes. Once I saw him in a red cloak and I had never seen a more handsome than him." (Sahih al-Bukhari)
Assuming you've really seen the prophet Muhammad () in your dream the most important question now is what will you do in future? This vision might be a blessing for you and a wake up call, you might take it as a an advice to learn more about Islam and try to make the best of it or you might leave it and say it was a dream.