Yep - absolutely avoid a shotgun as a starter mic. If you lived in the UK, I'd happily loan you a hand-held and a shotgun, and I know you'd not then go and buy one.
If you want sensible choices for spending with a hearing issue - a Shure SM58 from a real audio dealer, NOT ebay, and a really good set of headphones, ideally ones that go over your ears, seal, and cut out the sound of the room, or even in-ear style ones with expanding foam seals to replace any hearing devices you may be using. This is important because hearing aids that use even decent microphones, get optimised for your hearing curve, and wreck music and speech recording, where you need to make choices. When I was teaching we'd have students doing music technology who discovered that with typical tools found in music DAWs they could enjoy music so much better by producing the right response curve for in-ears. Shure 215's were very popular for this, and they'd set up plugins on the college computers to load in their own EQ. The majority would then be able to produce really good mixes, once they found the right settings.