I have read that these entities tend to pretend of giving good vibes in order to establish a connection.
This is absolutely true, and we need to be extremely cautious about such things. As well, some people will be given "psychic gifts" that work for a while, then seem to diminish. This is a tricky trap, and i caution everyone to take your ascension in reasonable steps.
The bible speaks about how the devil and demons can immitate an angel. As we approach higher ascension, note that the "battle" is heating up. Every trick in the book is being pulled out to fool the serious sojourner. How do we discern the "good" from the "bad"? Ye will know them by their fruits.
Higher dimensional sentinces have no problem with you questioning intentions, reasons or anything else to put your experience into honest light.
Energy vampires will divert you attention/questions away to something else, rather than be straightforwad with you.