While it may seem like you made decent progress through the map by the time you claim the speed booster, you'll actually have to backtrack to continue the game. In the game's starter area, Artaria, there were many speed booster blocks placed around that prevented you from accessing certain locations. Now that you have the speed booster, you can access these areas, giving you more of the map to explore.

For those not familiar with the franchise's previous installments, much of 2D Metroid games is unlocking previously hidden areas of the map and requiring you to often revisit areas of the map you've previously been to. Traveling back to the Artaria section of the map will allow you to advance further in the game's storyline.

Once you reach Artaria, you should be able to break through the speed blocks in the upper-left side of the map, which will give you access to a new section of Dairon.

After this, you should be able to advance and then unlock the grapple beam, another useful item you'll need to complete the storyline.

Metroid Dread is now available for the Nintendo Switch.