Hello. Well as I mentioned in my other posts, I've been through depression. So I know that due to it my sleeping habits changed. I began sleeping too much.
But now since around the beginning of this year, I've been having allergies. Every time I was around the allergen, I had trouble breathing. My chest would feel tight, and I would kind of gasp a little for breath. The problem is that when I sleep, my chest seems to collapse, kind of feel like it sinks down. So then in the morning I notice that my breathing is slower than normal and my chest feels collapsed... so I have trouble waking up like normal. I even sometimes wake up trying to catch some breath. Also since at least three months ago I haven't had any allergies anymore, but that problem seemed to stay.
What do you think it could be?

I honestly have no idea what is going on with you but I do know that this is not normal. You should seek advice from you health care provider as soon as possible. I wish I could put you at ease more! Good luck!

Does this at all happen or has happened to anyone??

Other than the "collapsed chest" feeling, your symptoms sound similar to Sleep Apnoea.

Here's a link:

Sleep Apnoea FAQ / Sleep Apnea FAQ

I read the page, and I found that it sounds pretty similar to my symptoms, I usually do wake up very groggy even dizzy not feeling like I had a good rest even if I slept 10 hours.
Thanks a lot for the suggestion, next time I go to my doctor(which happens often) I'll be sure to ask him about it, maybe he could refer me to a specialist. Thanks.

Yes, you should see your doctor ASAP.