I forgot to create a home partition during the installation of ubuntu 17.04, Whether it will cause problems?
No it will not cause any problems when running Ubuntu or when performing regular release upgrades. The only thing you need to take care of is that you don't format this partition in case you will re-install Ubuntu in the future.
You can always move home to another partition or drive later in case you really need this. This could in theory also be done from shrinking an existing partition but in case this was a fresh installation a reinstall is probably the least time consuming procedure.