Macbook slow to start-up and displays unusual start-up screen

Hey everyone,

For the last week or so my Macbook has been behaving strangely when I start it up from sleep: it displays the screen you would normally get after your battery has fully emptied and you have just powered up your computer again (I'm not 100% sure if that makes total sense..it's the screen with the white bars on the bottom that slowly fill up before it takes you to your login screen) This only happens when my Macbook has run out of charge and automatically goes to sleep and then I plug it in and power it up again, which is why I'm concerned because my computer is plugged in when this happens + the battery is fully charged. Also, the computer is very slow to start up and takes about a minute before I can properly log in (the screen freezes, sometimes it goes black for a couple of seconds and then it goes back to normal) and finally the computer seems to be a bit laggy at times and slower than usual. I have already verified my disk and repaired all the errors that came up (using Disk Utility), and this doesn't seem to have fixed the problem.

I am very confused and cannot figure out why this is happening; I've bought my Macbook only a year ago and I always take exceptional care of it. Has anyone else come across this problem before? If anyone could provide any input or help me figure out the cause, I would greatly appreciate it.

Thank you for your help in advance 🙂