Have you made significant changes to your Project since it "worked well untill this week and everything is very slow i cant move things "?
MIT has not made any changes to App Inventor in the past few weeks so this might be a hardware issue on your end, and increase in the number of blocks or resources in the Project etc.
Is your Project increasing in size (e.g. number of Blocks etc.)? Performance of the compiler's Designer is influenced by the number of Blocks; for instances as that number approaches about 7000 developer's screens get slow.
Has your router speed changed ? Are you sharing your network with others who are gobbling up bandwidth?
Have you added a browser plug in that might be affecting performance or have you changed your security program that might be continually checking data flow?
You might switch from Firefox to Chrome browses or vice versa. This sometimes helps with a performance change for some users.
If this is a Blocks issue, sometimes collapsing Blocks helps as eliminating unnecessary blocks (re-using blocks as Procedures etc. to reduce the total number of Blocks.
You may be able to ameliorate a situation like this by NOT developing live (using Companion). Develop without Connecting. Make code changes and then Compiling, install and test.
What you might be experiencing is a limit as to the size of your Project if this is an 'excessive' number of Blocks issues. App Inventor does have limits.
Regards,