Thanks, I had a listen to your clip. Your voice is not one I'm familiar with, so I'm not too sure what's going on. I notice a few things though:
1. Your singing sounds both tense and "dull". I think those are related. The "exciting" sound in singing comes when your voice sounds free.
2. Judging by your vowels, your larynx is rising up. This makes you need a lot of force to hit higher notes, and also makes your lower notes tense. Fixing that isn't straightforward, there's no "quick fix". The problem is that as you lower your larynx, you also need to engage other muscles to connect your vocal cords again, so it's a tricky process.
3. Your singing is pitchy, but I think that will fix itself when you free up your voice.
If you can afford a teacher, get one

If you can't afford a teacher, you can try the first exercise from those Seth Riggs videos on youtube (the "lip roll"). That may help you to relax your voice. Even better, make a recording of yourself doing the exercise and send it to me. Maybe i can hear something in that that I can't hear in the clip you posted.