I agree with all of the technical advice given.
I however see that you say that your photos are "pixelated", so the only other thing I would add is to make sure you always shoot the largest format your equipment will allow.
Try this link (It's my gallery but you can click on "Forums") go to Nature/Wildlife.
The nice thing about this link (I've been a part of it for 12 years) is that if you see something you like, ask the person that took the exposure what his settings were. After that, start with his reference and play with the values until you get the results you are happy with.
http://www.fredmiranda.com/hosting/showgallery.php?mcats=all&si=&what=allfields&name=Steve4&when=&whenterm=
I've been doing this for over 30 years and understand the initial frustration to figure it out. Just keep shooting and take notes on your exposure values for reference.
If you have any questions bump me on here and I will help as much as possible,
Steve