thumb injury plz help

Okay...

1. A bell from my ice cream cart hit my thumb a couple of weeks ago (8/16)

2. I thought it was just a bruise bone but nothing serious. It's in the metacarpal joint area. I put ice on it everyday. Until...

3. I started moving and jerking it around like two weeks later to see if it was fully healed (9/2)

4. The next day at work it felt stiff and was hurting (9/3)

5. It was still stiff and hurting and feeling stiff/weak for a couple of days until I put a ACE thumb immobilizer on it (9/7)

I'm planning on keeping this thumb immobilizer on for six weeks and then relaxing for another six weeks. I CAN'T see a doctor so I don't know how serious this is or what's the right thing to do.

Should I wear it all the time? In the shower?

This injury has had me worried. I don't want to lose my guitar hobby.

Please help. What's the best way to treat my thumb?

Thanks