Realtor stealing my offer for himself

[Albana NA]

Hello guys I’m just a little bit confuse I was dealing with the REALTOR  and I trust him 100% apparently I found a house I really like it it needed some renovation though,

anyway so we were talking about the price to make an offer for the house and apparently we agreed to the price I wanted but two hours later he called me and he told me the offer it’s too low we cannot do that  because they will not accept the offer, so he was telling me we should give almost $100,000 more and I refuse for that  but what he did he went behind my back and he bought it The house for him self for the same offer I told him to buy it for my self.

So I’m just trying to figure out is this legal for what he did to me, or what should I do please guys need your help