24 weeks, baby moving a lot more than usual?

I'm 24 weeks and today my baby has been moving a lot more than she would usually move. I have walked around, sat down, (which usually stops her movement), but she's still going. I also noticed that all day, each time I go to the rest room to urinate, I feel a lot of pressure on my lower abdomen, as though she drops dramatically, but just a few minutes later, the pressure goes away. This is my first pregnancy, so bear with me ladies (and gentlemen in any). Should I be worried? I know that if I feel decreased fetal movements I should be worried, but does it work the same for increased?
Please help. I'm not sure what to do and I'm starting to get worried.
Thank you for your help!
I also noticed that when I sing to her or just talk, she stops moving for a bit.
I have also heard that the baby should move a lot after an active day, but funny enough, today has been the first day in a very long time that I have lacked activity almost all day, with the exception of cooking which is not much activity! lol