The pearl doesn't have a lot of free memory. My guess is you're running low, especially if you're saving all your texts. Go to Options---Status and check the file free number there. Anything lower than 12mb and you're going to start running slower. You can delete texts, delete apps you're not using, and do a search for "memory optimization procedure" to do even more. A battery pull a day also helps greatly.
Also make sure that pics are being saved to the media card and not the device memory. Make sure you properly close apps by hitting menu>close rather than hitting the END button. There is a thread called "How to increase blackberry's file free memory" on here check it out. It is linked as memory optimization in my signature. It will help you increase your memory.
You can also download an application called Quickpull. This will basically do a battery pull for you, everyday at a scheduled time. I set mine for 5:30am everyday, it works great. Basically you start each day with the max amount of memory for better performance, instead of having to remember to do a battery pull (or be forced to) every other day or so.