Kateycrunch, it shouldn't hurt when you sing. In a big group, the leader maay not be aware if you're straining your voice in some way. It might be worth having an individual lesson or two, just to check out how you're using your voice and establish what your natural range is. I would endorse the suggestion of looking at the Natual Voice Network, and seeing if there's a teacher in your area.
For our generation, it may seem self-indulgent to have singing lessons. but many of us paid out for years so that our children could learn piano, flute, trampolining, ballet, etc. If you can afford it, it's your turn now!