Welcome!! I am still a newbie with my 7 week quit. But I totally get your tiredness of the cigarettes. I have smoked for ~45 years before I was brave enough to quit. But not after I searched the internet and found this forum and the website whyquit.com. Read as much as you can. Understanding the addiction to nicotine and what nicotine as a chemical is doing to your brain and body was extremely helpful for me to get over the tough times. There are -also via this forum- a couple of helpful video's on how to navigate the first days and to minimize the side effects of withdrawal.
Don't think that it is harder for you because you smoked such a long time. There are people on this form who also quit after a long smoking history and they succeeded.
Yes, the beginning is tough but it will get better. It takes time (and patience), but it will get better as long is you do not get any nicotine into your body.
Writing about your quit is helpful too. If not on this forum, keep your own little diary. Especially looking back and see what you have achieved already is fuel into your quit.
Quit smoking is a gift to yourself! But give yourself rewards for the fact you have not smoked. Be nice for yourself. Spend the money you saved to something nice or fun.
Did I already mention that no longer having cold feet all the time is sooooo comfortable? I know there is much more but that was the first improvement I noticed. And actually pretty quick after quitting.
Let us know how you get on. There is a lot of support here!