A vocal trainer will teach you the proper breathing techniques to improve these skills. It will be much easier for you to play notes and successfully sing your favorite songs. Find a reputable vocal coach who works for you and works with him for a while. It will work wonders with its sound and, if you intend to sing for the rest of your life, it will teach you how to keep your vocal cords fit and healthy.
I've never had them, but a good friend of mine did. It helped him overcome his stage fright and get good enough in his own mind to really start singing. He was also very good after the lessons, whether it was his technical skill or just the improvement of confidence which changed I don't know, but in his case it was definitely worth it. Singing lessons are worthwhile because they give you the opportunity to improve your voice through training and practice.
For me, the voice classes paid off. Ask anyone enrolled in singing lessons and they will tell you that their vocal performance changed dramatically before and after singing classes. However, voice classes can teach you exactly how to use your lungs in the best way to get the maximum sound out of every breath. Whether it's something you do just to feel good or something you do unconsciously, there's no immediate need for you to search the internet for great vocal lessons.
Due to the number of people who want to learn to sing and the vocal coaches who want to take advantage of this need, there is no shortage of the best online singing tutorials. In addition to avoiding vocal cord nodules, knowing the right vocal techniques will help you improve the quality of your voice faster than you would if you did it alone. Vocal training involves the whole body and you will be instructed on correct posture, breathing and vowel shape. Vocal cord nodules (these are painful lumps on the vocal cords that you can easily get if you keep singing without proper knowledge of vocal techniques).
You can even book with me on Skype for a personalized singing class focused on building your own vocal base (just use the “book” button on the top menu of this page). Everything you need to know about the voice, whether it's singing or something as simple as everyday speech, count on a vocal coach to know a thing or two about it. I wasn't a natural singer at all either: I struggled with tension, I couldn't play the high notes, my tone was lousy, I used to go hoarse in the middle of a show and I really hated my voice until I developed my vocal base. If you feel like you've hit the vocal wall, consider booking your first class at the Ramsey Voice Studio and see what you're missing.
By taking singing lessons, your coach will be able to listen to the way you sing and correct your tone and tone, speeding up the process until you can do it on your own.