what the heck is this?????

[Amy_Lee]

  OKay for about 4 months now I have been getting this ache(it's not really a pain it's just a constant dull ache) on my left side right under my boob...  I don't know what it is, but it's getting annoying... I am going to ask my OB about it next time I go in, I was just wondering if anyone else has/had this and maybe knows what it may be...