Am I playing the game wrong?

[Ronduwil]

I have a ps4 account I have been playing on and for some reason I am behind on xp I was also for some reason robbed on tombstones when going through castrum and prae getting only 100.

I don't think you were robbed on tomestones going through castrum and prae. The 100 tomestones that you got were for running it for the first time. The additional tomestones aren't granted when you queue directly for one or the other. You have to queue for a random MSQ via the duty roulette to get those. You also get a massive XP bonus for the first random roulette of each type that you run each day. At low level, you can also run levequests to catch up if you fall behind. Also, be sure to log out in a rest area (like a city or an inn). Look for the moon icon next to your XP bar to determine whether you're currently in a rest area. Logging out in a rest area grants you a massive XP buff whose duration depends on how long you were in the rest area.

[Tahbitha]

For whatever it's worth, I'm a new player too. Level 54 Dragoon, just finishing up ARR.

I started out doing every sidequest I could find but I noticed by around Level 15 or so I was starting to outlevel the MSQ so I dialed back to just doing the MSQ and job quests. It took a bit but eventually the level of the MSQ "caught up" to me. I'm currently running Level 50 quests at Level 54, so still just a tad ahead but not so much it hurts the experience.

I'm starting to mess around with other jobs, and I plan to do sidequests then.

[Faafetai]

I don't think you were robbed on tomestones going through castrum and prae. The 100 tomestones that you got were for running it for the first time. The additional tomestones aren't granted when you queue directly for one or the other. You have to queue for a random MSQ via the duty roulette to get those. You also get a massive XP bonus for the first random roulette of each type that you run each day. At low level, you can also run levequests to catch up if you fall behind. Also, be sure to log out in a rest area (like a city or an inn). Look for the moon icon next to your XP bar to determine whether you're currently in a rest area. Logging out in a rest area grants you a massive XP buff whose duration depends on how long you were in the rest area.

It was I think 100 for castrum just queueing up and 200 for prae at the time so it should have been 300 like the other people who I ran it with. They ended their first time with 300 tombstones total and when I looked at my currency I only had 100 tomestones. I usually don't pay attention to that sort of thing so I would have just gone through not even noticing if someone didn't say oh wow if we run msq roulette I could afford a weapon. I looked at mine, and realized something was weird. It wasn't that big of deal, so I just ran msq roulette and again the next day to have enough for the weapon. Also aye, I ended up just running leveling roulette twice, but I didn't realize I would be behind half a level just going through msq. I think now they give you 200 tomestones for each one looking at my duty finder. So thats cool they boosted that I know some of the other roulettes got a tomestone boost too not a huge one but a nice little boost compared to how it was pre endwalker.

Oh and the challenge log fates that bumped me where I needed to be, but I think at the time square probably assumed you would stop to try out Fates and stuffs so the xp wouldn't be a problem. For my main account I was doing a bunch of side quests when first starting playing, so I was overleveled to 55 on bard by that point and ended up realizing I missed playing tank.