English to Italian Other General / Conversation / Greetings / Letters

Fifteen years ago I worked as a microbiologist in a laboratory that dealt with quality control of food products. As the boss tried to compete with other private laboratories, I became Gill of all trades. Had to do also chemical tests of water, qualitative and quantitative analysis of food products and beverages. I spent the days in feverish activity and turned restless.

Gentilissimi traduttori,
Sto scrivendo una lettera alla mia cara amica Francesca. Vorrei scriverle i suddetti fatti. Come rendere in italiano l'espressione "feverish activity" (i.e. having many things to do at once)?
Grazie in anticipo.