Hi BowtothePhoenix,
This kind of dull pain can be from two reasons. The first is a mattress that is softening which can end up with your hips flexing beyond their “neutral” range. The second is that in some cases when the upper layers have softened and you are “going through” them more into a firmer layer below … then this can lead to pressure problems. The first is more difficult to “fix” because it is mainly a support issue which may require firming up the support of the mattress while the second in much easier because it is a pressure relief issue which can be 'fixed" with a softer topper.
A topper can work well and with better quality materials can even help with the first issue in the short term. This is particularly true of latex which even in a comfort layer and with softer ILD’s can be more supportive than other types of foam. As long as the support issue is not so bad that the flexible topper just follows and “bends into” any soft spots … then it can be a good idea … at least for a while.
It would help to know the mattress you currently have and it’s layering because what is under the topper may help identify what is happening and make a difference in what type and thickness of topper would be best.
I also agree with robbiev3 that Arizona premium has some very good value in latex toppers. There are also some very good options for a high quality memory foam topper if that’s the direction you choose to go. Post #4 here has some of the better sources for latex and memory foam toppers and of course there are other good choices as well depending on what you need. A forum title search on topper (you can just click this) will bring up lots of information about some of the choices that others have made as well.
Phoenix