I would like to know if I should expect any problems after I have done my meditation in the morning for a half hour? For the whole morning afterwards, my mind felt very slow to think of anything. Is that a good or bad sign?
Re: mind feeling "very slow", "very slow to think of anything" -- when someone tells you something, can you reply immediately without thinking? That's a sign of good meditation.
If your "very slow to think of anything" just means you are going around basically without thoughts, and you can respond to anything spontaneously with no blockages / no doubts - that's good. While, if your "mind very slow" means you can't respond - that means your meditation was basically cultivation of sloth/torpor.
It is said, if your meditation is wrong it can be a cause of being reborn in an animal world! Meaning, if in your meditation you generate "laxity", then you are only training in making your mind dull, like the mind of a cow or sheep! So you need to know what is laxity in real experience, and must be able to recognize it when it arises. Laxity is when your mind is not sharp and bright during meditation. Meditation mind should be very sober, not like a drunk mind or sleeping mind.
If "slow to think of anything" means less distracted thoughts then that's good. But if that means your overall awareness/mindfulness decreases instead of increases then you might want to check your meditation technique. A nice effect of meditation is a decrease of the Five Hindrances: desire, ill-will, sloth/torpor, restlessness/worry, and doubt. (ref: The Five Mental Hindrances and Their Conquest)
Since this episode when you wake from sleep are you groggy and tired or relaxed and alert?
The lack of activity isn't an indicator of anything, the quality of the mind and body is.
Do you see a decrease in sense desires and aversions? Do you see a decrease in any addictions or obsessive habits, such as checking your phone for notifications?
This can be a very good sign if any of the above positives are true. Otherwise something is seriously wrong with your meditation technique, but not to worry such errors are early corrected.
Because you're grinding through it rather than being relaxed and clear and enjoying it
Simplest way to fix it is after you've done your stuff, take a small break, then focus on the meditation point and notice how it feels as you focus, then drop the focus and rest a second and focus again. Notice that how you focus affects how you feel when you link to it. Try lots of different ways and at some point you'll hit on one where it feels 'exciting' and 'clear', then stick with that onhe