It seems like after not seeing him very much (atleast not in an environment where it is normal to speak to him) you were excited to finally be back at college so you could see him and speak to him in a way that didn't feel awkward or weird. After that sudden exposure, you started thinking about him more, and then you had a dream about him. It's very cute that you did too

I know you probably wanted an interpretation that looks like it was copied and pasted from a dream dictionary, but...you know, this just says to me that you missed being able to chat with him, and spend time with him (you didn't do anything sexual, so it wasn't infatuation that caused it otherwise you'd be having naughty thoughts)
Oh well...I have a crush on a professor too...is yours cute? hahahaha. That, in my opinion, is the important question here

sorry if you get offended...but hey mine is cute, and I had a dream about him just like yours as well...hahahahaha.
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