Some babies do drop the nap around two. It can be frustrating for Mom, but some babes just don't need it any longer. You know your LO best so I think I'll leave that one with you.
At 26 months, your son is definitely old enough to know which parent he can get to give into him and it's often Mommy. Tracy suggests you teach your LO to gradually stay in their room for longer periods, knowing that you will eventually come back. You can start by doing this during the day, leaving your LO for 2 minutes after some good quality time. You need to tell them you're going to go to the bathroom, do the dishes etc. for 2 minutes but you will return when the timer goes off and you must return as soon as it goes off. Once your LO is more comfortable with this during the day, you can move it to the night time. The difference is, you do the usual bed time routine and explain to your LO that you will sit with him but only until the timer goes off (Tracy suggests 2-3 minutes). When the timer goes off, you say good-night and leave. If he cries, go right back in and say you'll stay with him for a few minutes and then you're going to leave. You may have to do this several times but he will start to realize that crying isn't working anymore. If he marches out of his room, take him right back with no conversation. You have to be firm on that, because engaging with you is what he wants. It may take a few nights, likely at least two but if you're consistant, your LO will learn that bed time means bed time. I hope that helps!