Welcome Honeybee,
I have been on Humira for 3 months and on 100mg of Imuran to help manage 3 fistulas. My experience with Humira while it hasn't been a fantastic remission/healing story I have been able to cope and manage it pretty well. The major side effects you are probably reading about are extremely rare and all those crazy warnings the pharmaceutical companies are required by law to issue them to the public and ensure the patient understands the risks even if there is a 0.00000000001% chance of anything happening. My only main advice for issues like TB is make sure you are up to date on your vaccinations before starting.
If you notice anything strange just always talk to your doctor or head to the hospital - I have once and it turned out to be viral gastroenteritis and managed to recover in the same time period as a 'normal' person regardless of being on Humira and Imuran.
The more minor side effects can be annoying sometimes I found that after the few initial injections I was absolutely exhausted and having horrible diarrhea a few days post injection. These things have eased off over time and I hope they get better until I switch to remicade in February.
For the injection itself I started with the pens and about to switch to the syringe. Why? because the pens can sting like nothing you would believe for those 10 seconds and I had a habit of misfiring the pen - I always flinched and pulled the pen away so never got the full dose (luckily I was able to replace the pen!). My brother (also has crohns) now does it for me. I close my eyes, and have a jellybean to bite down on and chew during those 10 very long seconds.
If Humira works for you it will be wonderful and the small bumps will make it all worth while. There is a great support network out there for those of us on Humira so please don't worry to much - keep up your normal daily routine and keep in contact with your doctors. I hope that the Humira will be the right treatment for you!