Fibrin hydrogels prepared from different fibrinogen concentrations (12.5, 25 and 50 mg/mL) were studied through oscillatory rheology (gelation kinetics, stress amplitude tests and frequency sweeps), static experiments (creep and recovery tests) and turbidity (gelation kinetics). The experimental parameters obtained from these measurements (including gel point, characteristic times for different kinetic phases, loss and storage moduli), were used to gain some insight on the processes concurring to form the network structure of fibrin hydrogels. Here, we show (turbidity measures) that lateral fibre aggregation appears to be significantly depressed with increasing fibrinogen concentration. Among other important findings, a caveat in using absolute data of mechanical properties from gelation kinetics: we have shown that at low fibrinogen concentration, the actual modulus values are significantly affected by the application of shear stress during gelation.