Should I Take Penicillin After Having Undergone Splenectomy?

i had splenectomy 4 years ago to cure ITP. my platelet counts were normal as i had a course of penicillin but now again my counts stay in the range of 20-50. I am about to start a job in an oilfield as an engineer. Is it safe for me to do so?The job is kind of tough like staying up at night and hammering and stuff. Will the toxicity of gas effect my counts? what else can i do to keep them normal? i do not want to take steroids.
my throat has also become very sensitive. I presume it is due to my weak immune system. Furthermore my lymphocytes are 12%.

Please suggest me something and give additional advice if u have any. I am 24 years old male