Sounds like he's frustrated. I know DS just wanted to walk - crawling was a poor substitute but it worked for a while IYKWIM
With DS, I give him things to do that are suitable for his ability, so at that level, I put some things around for him to pull up on - favourite toys on chairs were a good one for us, kept him occupied for a bit trying to get hold of the toy... then as he got better at it, he'd walk around the chairs getting all the toys. We climbed the stairs every day til he got bored with it, did lots of 'jumping', I lay on the floor and let him climb over me, swimming is a hit here too. Swings at the park (the baby ones) were a fun at this stage. Water in a container with a couple of cup measures/spoons/whisk or whatever was good too.
