Slow movement speed

I've been on the snapshot, 1.16, and other versions and I've played single-player, multiplayer, and LAN worlds. I am noticeably slower than I should be and I am slower than mobs and even other players. I can't fight creepers because I can't move away fast enough after I hit them and they start to explode but I can on other PCs. I also ran next to another player and they were running faster than me by an estimated %25 and I don't know what is wrong. It's also not my frames bc I keep them on my screen to make sure that's not the problem.