I'm not the best person to tell you about chemo from the personal perspective because I don't need it. I had an Oncotype test which ruled it out for me-in a good way (I was a Stage I breast cancer). I did have a unilateral mastectomy.
But I'm a trained Medical Librarian, and as such can convey information and referrals (not medical advice). The information I want to give you is to tell you to wait (hard to do) until you see your Oncologist before leaping to any conclusions (unless your breast surgeon indicated something to you re you having to have chemo). The referral I'm going to give you in case you need chemo is for a book called "I Word Lipstick to My Mastectomy" by Geralyn Lucase. It was written at least 10 years ago so you'll find it on Amazon or other booksellers fairly inexpensively if you buy a used copy. Geralyn had breast cancer at age 27 or 28 and she chronicles her experiences with chemo. Chemo is a highly personalized experience, i.e., it's different for everyone in the same way that injections or childbirth is different for everyone. Some people are not so affected, others very much so. You'll have to wait and see (if your oncologist decides this is the route for you) until your first chemo treatment to see how it goes. Remember they have fairly good drugs now to help control side effects so be sure to let your doc know what side effects you had following your first treatment when/if they happen.
Hope my advice helps a little. No one can tell you how chemo's going to be for you because it's different for everyone! But I wish you lots of strength, health, beauty and humor while you're going through this.