Should I be concerned about my agent not being honest?

We placed an offer on a house and was told by our realtor that it was denied. We thought it strange that we didn’t even get a counter offer as there was only 3 offers. House closed $5k more than our offer.

Second house we were interested in our agent called their agent and told us we were only paying for the land as the house is in habitable so we didn’t go see it. House closed and new owner is living in the house.

The third house we told her to place an offer or $475k which was $25k over asking. She said the agent said they had multiple offers so unless you were going to come in at $505k you had no chance so we did not put in offer. House closed at $480k.

Are these occurrences common? Should we be concerned that our agent is not being honest? I would think he would want to do everything to get us a sale. Is it acceptable to reach out to seller directly to ask about the offers to see if agent is being truthful?