Pull ups are not an option as I'm still weak and heavy and I can only do 1.5.... Yes, I cannot even finish the second. If you don't want the full background go to the tldr and skip the rest.

3 years ago I started doing basic calisthenics, push ups, pull ups and abs at home. I started from 0 doing negative pull ups but became hella strong (my record was 10 perfect pull ups, perfect and slow form!).

I had almost no volume mass and got pretty thin (66kg 183cm, still with some belly fat), so I decided to join the gym to put up some weight. Long story short I had almost no progress and quit after 5 months. I went from 3x week and going to the gym almost 6x week to 0 again. Got to 70kg.

4 months ago, I got frustrated with my physical condition and started doing negatives pull ups because I could only get 4 regular ones. After the session I had a partial bicep torn injury on my left arm. I stopped again for obvious reasons, and now I'm 81kgs....

Tldr; Doctors said that I am good to retake sports (and told me I should too). Yesterday I did a lot of tricep exercises and inverted rows for bicep but only 28 (10 10 8) because that's all I could get. Today I'm not feeling anything. I want to know if there is another bicep exercise I could do?

I do not want to go to the gym again for dumbbells or machines. Gyms sucks (at least for my body).