Bad Chemical Taste

You'll be fine. I do a lot of low and slow cooks and i always clean it out before those. Probably once a week or 10 days. If you are just grilling, you can probably just sweep out the ash box every 2-3 cooks and not worry about taking it apart to clean for a while (maybe 10-15 cooks). If you notice trouble getting up to temp or fires burning out at low temps, time to clean. I clean mine out all the time- it takes 5 min and I hate messing with fires that don't act right. When I'm just grilling, I'll go quite a while without taking it apart. I sweep out the ash regularly though.

so when you say clean you mean take all the charcoal out and make sure holes are clear etc.

When I say clean out, I mean to pull everything out of the egg and sweep it out completely. Once you get more comfortable, you'll know when it needs it and when it's OK. If you aren't sure, spend 5 min and clean it all the way out. Also, like Stike said, fill it up with good lump. I would recommend (and there are many camps on this so do what makes sense to you) to only use larger chunks of lump for now and never dump the end of a bag in. The tiny bits and shake just clog everything up. That will fix your airflow problem and you can start tweaking it your way from there